With new breweries popping up on seemingly every block over the past decade, growlers have become the best way to bring fresh draught beer to parties, movie nights, and beach trips. But the typical glass models provided by most brewpubs aren’t meant to keep your beer cold for long, so if you have to travel a few hours to your friend’s barbecue, you run the risk of showing up with a flat, lukewarm IPA. This has created a need for a better, insulated growler that can keep beer—or anything else—colder for longer.

Stanley, the company that perfected the art of keeping drinks cold (or hot) for days on end, has a solution in the form of their double-wall insulated Easy-Pour Growler. Holding 64 ounces of liquid, this growler is built tough. It’s not necessarily heavy, but the construction is strong enough that you won’t have to worry about simple drops or cracks getting the best of it. The handle is securely bolted onto its stainless-steel body, and the lid has a latch that closes it up tight to keep excess air out. It's also dishwasher-safe, so you won't have to figure out how to scrub stout residue from the sides and bottom.

How the Stanley Growler handles cold drinks

In terms of function, the box says that the growler should keep drinks cold for up to 24 hours—but depending on your circumstances, it can go well beyond that. When I filled the growler with chilled water, it kept it cold for over a day and a half in my 72°F apartment; meanwhile, a glass of ice water sitting right next to it was tepid within hours.

After that, I left a growler full of cold soda outside from 9:00 a.m. to 5:00 p.m. during an 85°F day—when I poured a glass after work, the drink felt like it had just come from the fridge. With a lid that closes tight to prevent leaks, it’s easy to imagine slipping this growler into a backpack for daylong hikes or beach trips.

The Stanley Easy-Pour Growler is available in green, navy, and black.Stanley

But do the drinks stay carbonated?

A growler is not much of a growler if it can’t hold carbonation—but as long as you’re not opening and closing the lid ad nauseam, the Stanley does the trick. I tested it with a liter of Coke Zero (breweries aren’t allowing you to fill your own growlers at the moment), and after I let it sit in the covered growler for an hour, the first glass I poured was as foamy as something right out of a fountain machine.

Subsequent pours over the next few hours saw some flattening, but there was still plenty of life in each glass. If you’re looking to hold onto carbonation, the key is to fill the growler to the top to avoid getting too much air in it. And as if to provide audible proof that it’s working, you’ll hear a very noticeable pop when you open the vacuum lid with a carbonated drink inside.

The Stanley Growler can also handle the heat

The most surprising part of the Stanley growler is actually how well it works with hot beverages. I filled mine with boiling water at 8:00 a.m. before work on a Monday and clocked the temperature at 200°F. I re-checked the temperature every few hours and found that it would lose around 5 degrees every hour or so. By the next morning at 8:00 a.m., it still registered around 125°F, with noticeable steam wafting out every time I opened it. And because of its double-wall insulation, it was never hot to the touch.

Now, no one is going to drink anything that’s 200°F, but if you fill the growler with non-scalding coffee, it should definitely keep it nice and hot for the 18 hours the company claims (just don’t keep opening and closing the lid every hour or you’ll probably lose some of that heat faster.)

You can buy the Easy-Pour Growler on its own from Stanley’s website ($55) and Amazon ($55). It also comes in a gift set ($80), complete with four stainless-steel tumblers, which keep drinks hot or cold for up to 30 minutes and have built-in koozies around the body so your hands won’t feel a thing.