The Best Hard Cooler

Coleman’s Xtreme 70-quart 5-day cooler is our pick for best cooler because of its fantastic insulation, above-average features and affordable price.

Last Updated: February 27, 2014
After a few hours of further research, checking Coleman and Igloo’s lineup for new models, and making sure the premium brands weren’t offering anything more in line with our price range, Coleman's Xtreme 70-quart 5-day cooler is still the best. We also added some info about the Igloo Yukon line and some alternative uses for your cooler to try.

After over 20 hours of research and a week of testing, the Coleman Xtreme 70-quart cooler overperformed on its 5-day claim and was able to keep ice solid for a full week, all while performing nearly 20% better than its more expensive counterpart from Igloo. At $50 it represents a tremendous value for folks looking for a spacious, reliable cooler to take camping, or to keep tons of beer cold at a barbecue, or for those emergencies when your power goes out and you need to prevent food from the fridge from spoiling. Not only that, it’s sized so you can still move and carry with reasonable ease. It fits in most trunks and works great as extra seating.

How we picked

The purpose of a cooler is to keep things cold 1. The better the insulation is, the longer a cooler will keep something cold. Another way to think about better insulation is that it translates directly to needing or consuming less ice. Most of us don’t have a freezer that can produce enough ice to fill a cooler, and as such we resort to buying bags of ice from the grocery or liquor store. Those bags aren’t cheap (a 16-pound bag of ice at my local liquor store is $3.49, a 40-pound bag is $7). If you can use less ice or reload less often you’ll save money in the long term even if you only use your cooler a few times a year. One thing to keep in mind about size is that cheaper, less-insulated coolers are slightly smaller due to that lack of insulation, but it’s not noticeable as most of the size is determined by capacity.

We studied editorial reviews from outdoor and boating experts at The Boat Galley, Trailer Boats Magazine, Camping Life, and Slate, as well as plenty of discussion forums, most of which recommended the Coleman Xtreme, Igloo MaxCold, or the Yeti if you have the cash to drop. We then tested the cold-keeping power of three lauded coolers at the right price point — the Coleman 50-quart wheeled cooler, the Coleman 70-quart Xtreme 5-day cooler, and the Igloo MaxCold 70-quart 5-day cooler. To test, we filled them with 60 pounds of ice, leaving them outdoors with plenty of sun, and measured the amount of remaining ice each day for a week.

Our pick

The Coleman Xtreme 70-quart Cooler, along with the Igloo MaxCold, dominated cooler recommendations we came across in our research. Both the Coleman Xtreme and the Igloo MaxCold outperformed their claim of 5 days of ice retention, which is impressive on its own. However, the Coleman Xtreme kept ice for a full week (170 hours or 7.08 days) — thirty hours longer than the Igloo MaxCold (140 hours or 6 days). This is great news because the Coleman is cheaper than the Igloo, yet it performed almost 20% better. What was even more impressive was the gap between the lower-end Coleman and the higher-end Xtreme model, with the wheeled 50-quart Coleman losing all its ice after three days. Again, this is exciting because it definitively shows the value of upgrading to the 5-day models.

The Coleman Xtreme weighs about 12 pounds empty, and with 60 pounds of ice was still comfortable to carry. It measures 31.5″ long by 16″ wide by 18.25″ tall, and its design incorporates bevels and angles all over the place as well as a ruler and cup holders molded into the lid. Real insulation nuts will want to fill the cup holders with styrofoam, but given that how well it performed, it doesn’t seem to be all that critical. I also preferred the lid handhold on the Coleman. It resisted just enough without being bothersome. Additionally, Coleman’s Have-a-Seat Lid is listed as supporting up to 250 pounds.

The most noticeable and functional difference in the design of the tested coolers is in the drainage ports. Given that I was draining these coolers upwards of three times a day for several days straight I learned quite a bit about what works and what doesn’t. The Coleman Xtreme has a channeled drain, which made draining much easier and required very little tilting.

It’s also worth noting that the $50 Coleman Xtreme 5 performed nearly as well as coolers costing $350-$450 in a high-end cooler test done by where they ended up calling it the “best bang for your buck” amongst high-end coolers.

Flaws but not dealbreakers

Though the lid seals well, like other coolers in its price range, the Coleman lid doesn’t have a gasket, which could allow warm air or rainwater to seep in. However, its insulating power didn’t seem to suffer. Some reviewers also complain that its drainage port’s bilge cap is slightly flimsier than the Igloo’s cap.

The hinges on both the Igloo and the Coleman were really similar. Neither of them are terribly robust, and it’s pretty clear that this is where these coolers will fail first. The Coleman relies on a wedge built into the hinge to stop it from falling too far.

The handles on both were comparable and surprisingly comfortable for moving the cooler short distances. I would not, however, want to be stuck hauling either of these coolers much more than a couple hundred feet without somebody to help.

One thing that’s great about both the Coleman and the Igloo is that they feature user replaceable hardware. Some cheaper models don’t, but both the ones we tested did. This is important because the first thing that’s going to wear out in a cooler is either the hinges or the handles, and having affordable replacements is really helpful. Coleman offers replacement hinges for $5 and handles for $10 while Igloo has a parts kit including hinges and drain spout for $16.

To be clear, no coolers under $200 have really excellent hardware, and it’s clearly the place where they pale in comparison to their much much more expensive brothers from Yeti and Engels. With that being said, both coolers were easy to carry, had comfortable handles and featured drainage ports that didn’t leak, so even though their hardware isn’t top notch it’s definitely good enough.

Runner Up

Also Great

*At the time of publishing, the price was $55.

Igloo Maxcold Ultra 70 Cooler
Keeps ice for six days, drains fast, and is very well-reviewed by users.
The only other model with as many rave reviews as the Coleman Xtreme is the Igloo MaxCold. While the Coleman beat the Igloo in the ice test by over a day, the Igloo still managed a full six days of ice. The Igloo MaxCold comes in at 29.5” long by 16.5” wide by 16” high in a simpler, rectangular utilitarian design void of any markings or indentations. Like the Coleman, it weighs about 12 pounds empty and can be repurposed as a seat.

Another reason the Igloo falls behind the Coleman is the design of its drainage port, which lacks a channeled bilge drain. This means that it’s a pain in the ass to get the last few inches of water out of your cooler. Instead, the Igloo’s drainage port accepts a garden hose so you can drain the water away from the cooler. While this is cool, I don’t really see a use for this unless you spend a lot of time on a boat. Outside of that, the Igloo has a slightly wider diameter so it initially drains faster and it also has a screw-on cap which means the likelihood of accidentally unplugging the cooler is lower. Many reviewers pointed this benefit out.

Like the Coleman, the Igloo’s hinges and hardware are the weakest points. The Igloo has an additional plastic strap to prevent the lid from falling backwards and minimize strain. Between the Coleman and the Igloo, I slightly prefer the Igloo’s handles in part because it features hardware that allows you to install a rope. This means if a handle breaks at an inopportune moment you can fix it in the field with an impromptu rope handle, and if you want to lash it down you can. Like the Coleman, Igloo sells a parts kit including hinges and drain spout for $16.

What’s a 5-day cooler? How do you test it?

In order to differentiate between lower-end and higher-end models, Igloo and Coleman (among others) have adopted a strategy of naming and marketing their coolers after the length of time they can keep something cold. The models we tested claimed to keep ice around for five days and so the metric most often talked about when comparing coolers is ice retention. There is no formal methodology for determining ice retention, so we developed our own. It relies on draining and weighing the amount of meltwater produced at regular intervals.This measurement told us the percentage of ice that had melted up to that point in time. After measuring, we added the meltwater back to the cooler to keep the masses and energy consistent.

Why did we do this? In part, this methodology makes the most sense because if we relied on temperature (which is what most other published tests relied on) we would have seen a steady 32-33°F for nearly a week until all the ice melted whereupon the temperature of the water would increase dramatically. While this is somewhat useful in determining the total length of time ice is preserved, this doesn’t provide data capable of discerning the rate of ice melting. By measuring meltwater we can produce data that illustrates the relative performance of insulation between coolers over time. For example, after five days the Coleman Xtreme 5-Day Cooler retained 11 more pounds of ice than the Igloo. That translates to the Coleman being 20% more efficient overall in ice retention during the same time period. If we had just measured temperature, all we would have seen was five days worth of icy water with a temperature around 32 degrees Fahrenheit.

Cooler Performance Testing Methodology

We tested three coolers: the Coleman 50-quart wheeled cooler, the Coleman 70-quart Xtreme 5-day cooler, and the Igloo MaxCold 70-quart 5-day cooler. Prior to loading with ice, the coolers were pre-chilled with cold tap water (65°F) for 30 minutes until their interior temperatures stabilized. The coolers were then simultaneously loaded with equivalent volumes of ice (60 pounds of ice for the 70-quart coolers, and 42 pounds of ice for the 50-quart model). At regular intervals, the coolers were fully drained of meltwater which was weighed before being returned to the coolers. Meltwater was returned to the coolers in order to keep the systems stable across the week of testing. Testing was continued until all ice had melted.

As far as claims are concerned, both companies claim that their coolers keep ice around for five days, but Coleman is a bit more specific in that they specify 90 degree days. However, it’s not clear what that even means. Is it on days with a high of 90°F, or is it constantly 90°F for 120 hours straight?

During our testing, the coolers were kept outside of my house in Baltimore, MD and were fully exposed to sunshine and the elements in an open area 24 hours a day throughout the testing (with mostly hot, sunny days throughout the week). While this sacrifices a certain amount of experimental validity due to issues of repeatability, we believe the results are still useful because of the relative performance of the coolers. On days with rain or thunderstorms, the coolers were brought onto my porch as they lacked gaskets and it was therefore possible that water could infiltrate the coolers and upset the volume measurements. When the threat of rain passed, the coolers were brought back outside. The temperature range throughout the week saw highs of 80-90°F and lows of 64-72°F with a trend toward warmer temperatures.

Throughout testing we also considered and scrutinized how easy it was to carry both coolers when they were fully loaded, whether they worked well as seating options and how well they drained.

Why Igloo and Coleman are the leaders (in this price range)

The market for coolers today is still dominated by two names: Igloo and Coleman. Rubbermaid, a former heavyweight, no longer produces the same diversity or quality of coolers as they used to. In my research, nearly everyone recommended either an Igloo or Coleman within this price range, and whenever Rubbermaid was mentioned it was most often in the form of a criticism.

During my research I found heavy users of coolers and ice chests were skewed towards boaters, fisherman, hunters and campers. This population depends on their coolers to keep their catch fresh or their food from spoiling when out at sea or in the woods, and as such they place significant demands on cooler performance. Forum after forum and review after review, the same piece of advice was repeated over and over: get yourself a Coleman Xtreme or an Igloo MaxCold (or, if you have money to burn: a Yeti).

The market for coolers today is still dominated by two names: Igloo and Coleman.
Outside of forums, Carolyn Shearlock (who writes about living and cooking on boats at The Boat Galley) has a great writeup of what to avoid and what to look for in a cooler for food storage. Her recommendations were to seek out either the Igloo Maxcold or the Coleman Xtreme, saying “[the Xtreme is] what we used and block ice lasted 7 days in 90+ degree heat (and the cooler sat in a parked car much of the time so it was even hotter),”  However, she also mentions that if you need “something that can stand up to rougher conditions check out the Yeti.”

An article in Trailer Boats Magazine, which pit the Coleman Xtreme, Igloo MaxCold, Rubbermaid Durachill, and two marine models from Coleman and Igloo came to nearly the exact same conclusion. “For not much more or about the same price as the standard chests, the Xtreme and MaxCold are clearly a cut above the rest, and would be excellent choices for hot climates or extended trips where food and drinks need to be kept on ice for several days.”

Tom Bartlett of Slate also waded into the mire of insulation when he wrote up his experience with both soft and hard coolers back in 2006. Bartlett struggled with the Endurance model from Rubbermaid citing that “it will slightly but noticeably lessen the pleasure of being alive” due to its frustrating to open lid. He, too, eventually rates the Coleman Xtreme highest, explaining that “it stays cool for a long, long time. And in these increasingly warm times, isn’t that what matters?”

Lastly, Camping Life performed one of the more thorough tests online and came away feeling positive about both the Igloo MaxCold and the Coleman Xtreme, but found the Rubbermaid lacking with “the worst drain of all the units tested, requiring radical tilting to be fully emptied.”

What became clear is that both the Coleman Xtreme and the Igloo MaxCold represent a significant step up in performance from the base models without being significantly more expensive and so were clear candidates for testing. While some models of Rubbermaid were reviewed favorably, the one 5-day model they produce is only available at Walmart online and rarely in stock (there was a 10-day wait at the time of this review).

On another end of the spectrum, my research brought to light how popular super high-end coolers brands like Yeti, Engels, Brute and Icey-Tek are becoming. These tend to be highly-specialized (grizzly proof!), high-performance coolers that cost nearly 6-10 times what an equivalent volume performance cooler from Coleman and Igloo cost. That being the case, they fall outside the needs or price range of a majority of the people looking for a cooler which is why we didn’t end up testing them. We’ll mention a bit about what actually separates a Coleman from a Yeti later. It’s worth noting, though, that the $50 Coleman Xtreme 5 performed nearly as well as coolers costing $350-$450 in a high-end cooler test done by where they ended up calling it the “best bang for your buck” amongst high-end coolers.

Is it big enough?

Everybody has different needs, and as such we couldn’t test every single size of cooler on the market. Instead, we decided to focus on the most utilitarian and family-friendly size we could find (70 quarts). These are rated to hold between 100 and 114 12-ounce cans and ice (again, that number depends on how much ice you load). What’s nice about the 70-quart size is that 70-quart coolers are big enough for a variety of tasks. For boaters out there, Shearlock of The Boating Galley explains that “a 65- or 70- quart cooler is about the minimum size needed to have enough ice and space for food for a week-long trip for two.” Again, this is going to depend on how you pack your cooler, and how long you need to keep things cold (as more ice is going to take up more volume). Another example came last year during a power outage; I was able to store most of the contents of my fridge in a 70-quart cooler along with the necessary ice to keep it cold.

If you are looking for something smaller, Coleman’s Xtreme line comes in a variety of sizes including a 52-quart and 36-quart model with the only difference being that they’ve been scaled down. They have the exact same insulation with the only difference being that they’ll have proportionately more surface area to volume which might have a slight impact on performance. The 52-quart model would be good for a smaller family or a couple interested in camping for a few days, while the 36-quart is good for shorter excursions or as a second cooler for separating drinks and food.

One of the most important factors in deciding on 70 quarts in a cooler is that that is not too big. Anything over 70 quarts is going to present significant difficulty in moving, because of weight and ergonomics—these coolers start to get so wide that one person can’t carry them. As a moderately athletic six-foot-tall guy I actually found the 70-quart size to be pretty comfortable when it came to lifting and moving around by myself, even at 70 pounds. It also helps that the 70-quart size (both wheeled and non-wheeled) are often in stock at places like Walmart, Home Depot, and Amazon. While researching this piece the 70-quart size was referenced often enough that it seemed to solve the not-too-small and not-too-big Goldilocks dilemma.

Is a 5-day cooler worth it?

In order to identify whether there was a substantial difference in performance between a base model and a 5-day model we tested a non-performance cooler from Coleman and compared it to the Xtreme 5-day model. The results were striking. The non-performance 50-quart model from Coleman kept ice for just over three days. That’s not even half as long as the higher-end Coleman and Igloo. Furthermore, the base model from Coleman lost ice much faster in hot weather with nearly half of its ice melting in the first day of 90 degree heat compared to the 15-20% melted in the 5-day models.

This performance gap is significant, especially when you consider that upgrading to the 5-day line from Coleman or Igloo isn’t that much more expensive. It’s often only a difference of $10 or $15 depending on the size.

With that in mind, if you’re only ever going to use a cooler on day trips even cheaper coolers will be sufficient, including some higher end soft-coolers. However, when my power went out last year for five days I was happy my parents let me borrow their five-day model.

The bottom line: for $50, you might as well have a cooler that cools more reliably in case you ever need it to do so.

Marine or non-marine?

The last thing to address is the divide between marine and non-marine coolers. Marine coolers tend to be all white (why they don’t do this for all coolers for the sake of reflectivity is beyond me), made out of material that is UV-resistant, in possession of latches, and come with accessories that make it easier to lash down to the deck. Because they’re kept on boats they see a lot more sun than your Coleman out in the garage, and the marine rating ensures that it won’t fail quite as quickly due to UV damage. You can expect to pay a $30-$60 premium for a marine cooler over a standard cooler from Igloo or Coleman, so it’s not worth it unless you really are going to use it on a boat.

You can also find them in larger sizes as boaters tend to need upwards of 120 quarts to keep catches cold. Keep them in mind, though, as they frequently go on sale at places like West Marine and you might be able to score a deal on a larger cooler that is, for all intents and purposes, identical to the MaxCold and Xtreme line.

To wheel or not to wheel?

Because they can be a backsaver many people will be interested in coolers that feature wheels. When I visited Walmart, Ace Hardware, and Target I took a close look at what was available and came away feeling that the options from Coleman, Rubbermaid, and Igloo were remarkably similar. The wheels were almost always made out of cheap-feeling plastic, and none that I saw inspired confidence in long-term performance despite being described as “rugged”. Carolyn Shearlock of the Boat Galley specifically points out in her piece  that “wheels and axles on coolers tend to break easily on rough ground.” Her recommendation is that folks look into using a more durable dolly.

The second reason I stay away from coolers with wheels is that they can’t be used as seats as the added weight will snap the axle (most will have this printed on the cooler top). This is actually a huge bummer especially while camping (or at a party) where seating is scarce. With all that being said, both the wheeled Igloo MaxCold 70-quart and the wheeled Coleman Xtreme 62-quart are well reviewed on Amazon and look like good choices if you absolutely need the added mobility.

What does $400 get you?

YT65W_O-483x500Throughout our research there was almost universal praise for Yeti coolers (at least from those who could stomach the price). Nearly every publication that reviewed the Yeti scored it at or near the top. In two head-to-head tests with the Coleman Xtreme (one from Camping Life, and one from Sportsman Guys) the Yeti bested the cheaper cooler in terms of ice retention. But that could be because the equivalent volume model from Yeti costs about 8 times as much as one from Coleman. So, at the end of the day what does an extra $400 get you?

From the ground up, nearly everything in the Yeti has been upgraded. It has stronger hinges, a well-reviewed toggle latching system to keep the lid secure, a rubber gasket to reduce airflow and a variety of handles and accessories that offer wider utility for boaters, hunters and campers. Another big bonus is that the Yeti comes with a five-year warranty. For people who need the pinnacle of performance, and don’t mind paying through the nose, the Yeti is definitely worth looking out for.

Be ready, though, as the world of high-end coolers is fast becoming crowded. Similar recommendations can be found for Engels (especially amongst boaters), Icey-Tek and IRP, while newcomers Brute and K2 are just now getting into the high-performance cooler game. Almost all these brands tout the fact that they’re made in the USA, which is great but on par with the Coleman.

Igloo is also in the high-end game with its Yukon line, competing with Yeti; the 70-quart model goes for $333 on Amazon. This cooler is ruggedized, claims 7-day ice retention at 90°, and has stainless steel hardware. There’s also the Super Tough STX family; their 72-quart cooler retails for $110. Again, it features stainless steel, and is more ruggedized, but it only promises to keep ice cold for five days. We still don’t think it’s worth paying that kind of money for a cooler when the $50 Coleman will meet most people’s needs.

The last thing to note is that Coleman recently upgraded their Xtreme line by adding a 6-day series. These end up costing nearly three times as much (the 80-quart Xtreme 6 is $150 versus the 70-quart Xtreme 5’s $50) with the only notable difference being the addition of about 20% more insulation which should theoretically provide improved performance. Even the hardware like hinges and handles are identical. This places them in an awkward position as far as the market is concerned because they cost three times as much for only a modest gain in performance. As such, the reviews I could find online were mixed. For the price you’re probably be better off spending even more and going with a higher-end performance cooler if you really need the increased insulation.

At the end of the day, unless you have very specialized needs or absolutely have to have the best available, a $50 cooler from Coleman will keep things cold almost as long (or at least as long as necessary for most of us) as coolers costing many times more.

Alternative uses for your cooler

As Sweethome commenter steven75 points out, coolers can be used not just to keep beer cold, but also to brew it from scratch “I have two of these for all grain beer brewing. They are excellent as hot liquor tanks and mash tuns. The stellar insulation means less temperature drop during the mashing process (usually 60+ minutes) which results in higher quality beer.” Commenters in this Beer Advocate forum even suggest a blue square cooler like our pick for efficiency and volume. Popular Mechanics’ Andy Hill outlines the whole process of converting a cooler into a tun using a round cooler, not our Coleman. With some simple plumbing gear and a little bit of work, the cooler can filter out the liquid from the solids.

Additionally, you can turn an insulated cooler into a crude but surprisingly effective sous vide cooker if you don’t want to pay $200 or more for a dedicated sous vide circulator. Sous vide means cooking something super low and slow in a steady-temp warm water bath. Since coolers are insulated, they don’t only keep cold water cold, but can keep hot water hot, too.

Over at Serious Eats, J. Kenji López-Alt has dead simple instructions on the set up. You heat water a few degrees above the temperature you want the food to cook in and pour it into in the cooler — this accounts for temperature loss when the food is added — then seal off the ingredients in zip-top bags, toss them in, and close the lid. (He says this method is best for already tender meat, since tough proteins and vegetables take significantly longer.) Throw a steak in for anywhere from 45 minutes or 12 hours, and it’ll come out with the same quality as if you used a professional machine. Kenji’s takeaway from his experiments: “for those of you who have thought of playing around with sous-vide cookery (and I highly encourage that sort of behavior!) but have been thrown by the costs, this is a cheap, reliable, and pretty much foolproof way to do exactly what the more expensive machines do. Play away.” Per Se Chef Thomas Keller recommends a similar cooler method with vacuum packed food on the LATimes, using a 28-quart cooler which is preheated with hot tap water. Of course, our pick is pretty big. If you’re looking to turn a cooler into a sous vide, you may want to choose a smaller model, or be prepared to throw in a lot of water.

Make: magazine suggests turning a cooler into a worm composting bin, or repurposing it as a low-temperature curing oven. These illustrate the key point with coolers: the insulation keeps things at a desired temperature, hot or cold.

Wrapping it up

It’s always exciting to find and test a product that lives up to and even overperforms on a manufacturer’s claims, and both the Coleman Xtreme 5 and the Igloo MaxCold deserve credit for doing just that. It also helps when the more affordable option (in this case the Coleman Xtreme) does even better than its more costly competitor. It’s for this reason that we can heartily recommend the Coleman Xtreme 5 as a cooler to look for as things start to heat up this summer.


1.  A note on how coolers work:

The summer sun is so wonderful. Too bad it acts like a total jerk when you want to keep your beer icy cold. Thank goodness all you need is a well-designed cooler to help beat back that nasty heat. But how, exactly, does it work? The answer comes down to some very simple science!

A cooler is just a small, contained, insulation box. Basically a tiny version of your refrigerator (without the ability to produce its own cold air). Your cooler and your refrigerator, when it’s not turned on, use the same principles of heat transfer that a jacket, a blanket, or the insulation inside your walls use to keep heat in or out of a given place.

This all comes down to one, simple, and pretty annoying fact about how heat behaves (annoying if your goal is enjoying cold beer in the sun, that is): It flows from warmer to cooler areas until the temperature of both spots equalize. It’s the second law of thermodynamics — heat cannot flow from a cooler body to a warmer body (unless, of course, you have a mechanism that forces this to happen). Which explains why everything always eventually comes to room temperature when you leave it out in the open air.

There are three main ways that heat transfers from one object to another: convection, conduction, and radiation. Insulators rely mostly on the method of conduction and a little bit on convection (radiation doesn’t really come into play here, so we’ll leave that out).

Conduction works when molecules of two different temperatures come into physical contact. The hot object excites the molecules in the cold object, causing them to vibrate and warm at the point of contact. The vibration then gets passed along the connections between molecules in the cold object — conducting vibration and heat through the entire cold object and heating the whole thing up. This is how you boil water on your stove, except in water (and all fluids) the molecules aren’t in a straight line—they transfer heat by bumping into each other and tumbling around.

Fluids also transfer heat by convection. In liquids, hotter areas are less dense than cooler areas. Because of this, the hotter parts of the liquid rise and the cooler parts fall. So when you boil water, convection moves the heated water upwards, forcing the colder sections into contact with the heat source at the bottom of the pot. This eventually creates an equilibrium of temperature within the liquid.

Luckily for us, engineers have figured out how to control and manipulate the physics of heat transfer by setting up a barrier (or an insulator) between objects at two different temperatures (like your cold beer and the summer heat). The trick is to use materials that are bad at conducting heat, meaning their molecules don’t get very excited when they come into contact with hot objects. Plastic, styrofoam, water, and wool, for example, are terrible at thermal conductivity. Which means heat has a really hard time passing through them. If you create a barrier with one of these you can control heat. Wrap yourself in wool on a cold night and it keeps your body heat inside your blanket cocoon. Throw on a wet suit and your body heat creates convection currents in the thin layer of water between your body and the suit.

You can also make a barrier by creating a vacuum layer between your cold beverage and the heat. Your Thermos, for example, uses this method — by sucking the air out you eliminate all the gasses that could create convection and at the same time nearly eliminate all the molecules that would get excited and heat each other up.

Cheap styrofoam coolers are the simplest way to go about creating a barrier. Engineering on a larger scale generally involves plastic. According to Mike Brockel, Director of Design Engineering for Coleman, their coolers are built in layers — the case is polyethylene with an extra layer of insulation inside for some added heat protection.

So now that you know how it works,  toss some ice and beer into a cooler and keep the summer heat outside where it belongs. —Erin Biba Jump back.

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  1. Ice Chest Shootout, Camping Life, August 2, 2011
    "With the Coleman, the pro side of the ledger lists the solid feel of construction, the versatile lid with drink holders and a 24-inch ruler, the meltwater drain bilge, and the unit's towability..."
  2. Carolyn Shearlock, The Best Cooler for Food Storage, The Boat Galley, December 5th, 2011
  3. Tom Bartlett, Nice Ice, Baby: Which cooler is the coolest? , Slate, July 4th, 2006
    "It's less sexy than the steel-sided and harder to store than the Polar Bear, but it stays cool for a long, long time. And in these increasingly warm times, isn't that what matters?"
  4. Ron Ballanti, Playing It Cool: Which ice chest is best? , Trailer Boats Magazine
    "For not much more or about the same price as the standard chests, the Xtreme and MaxCold are clearly a cut above the rest, and would be excellent choices for hot climates or extended trips where food and drinks need to be kept on ice for several days."
  5. High End Cooler Test,, May 14th, 2010

Originally published: November 14, 2015

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