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If you were to search my Amazon order history, there’s one item purchased more than any other: a thermal mug. But only two of them have been sent to my house, while dozens of others have been sent all over the country as gifts.

It seems like an absurd exaggeration to claim that a mug can be life-changing, but I will stand by this statement until they pry my still-hot coffee from my cold, dead hands: The Zojirushi vacuum mug immeasurably improved my life.

The stainless-steel vessel is really more of a hybrid between a mug and a thermos, with the easy drinkability of the former but the shape and heat-trapping properties of the latter. It can take a beating; the locking mechanism keeps it from spilling; and most importantly, it keeps beverages hot for the better part of the day. These are surface benefits, though. What I learned when I started using the mug ran deeper than the light-blue paint on it: It became clear to me that the ability to drink hot coffee restores just a little of the humanity and order that parenting small children erases.

Zojirushi started out in 1918 in Osaka making a glass-lined vacuum bottle—the predecessor to my coveted mug—and launching a business that seems to prove my theory that the world runs on the ability to keep drinks hot. The same thermal properties of the bottle were incorporated into the company’s electric rice warmer in 1970, followed by the micro-computerized rice cooker in 1983.

But the durability I covet in my cup arrived in 1981, when the company put out its first all-stainless-steel version—eliminating the vacuum glass liner. Over time, the bottle got lighter, the nonstick coating replaced, the pour spout turned into an easy-to-sip-through opening, and the locking mechanism came into play: It is a virtually perfect coffee mug. As much as I covet a fancy $200 rice cooker or the new $250 toaster oven the company just announced (neither of which I have the counter space for), a $25 coffee mug provides far more luxury in my world.

The Zojirushi mug immediately proved its usefulness as I tossed it in my pack before heading out for a bike ride without having to worry about it spilling or cooling off. More recently, when I had to leave the house at 5 a.m., I made my coffee the night before to save time. Though no longer scalding hot when I grabbed it as I jumped in the car, it was still comfortably warm enough to have made the extra 15 minutes of sleep completely worth it.

But nothing has made it more valuable than motherhood. Having a baby tears away the body you’ve always been in and hands you a new one—one that belongs only partially to you. It is awkward and foreign and leaks milk and endless other bodily fluids you once had control over (or at least a heads-up before they left your body). Your brain, similarly, takes leave. It’s distracted, and even the simplest tasks—like remembering where you put your coffee cup down—become rocket science. A hot cup of coffee offers so much relief—familiarity and physical comfort, smells that signify normalcy, and of course the kind of mental boost that allows you put your shirt on both forwards and right-side out for the first time in a week. And yet it becomes a Herculean task that a new mom can find the time and space to drink a cup of coffee while it is hot.

My kids are older now, and I still dream of sitting down and drinking my coffee in a single sitting while idly scrolling the Internet, but my morning is spent chasing around two toddlers, who combined have about as much coordination as a drunk Weeble. So each day I put my coffee down—sometimes dangerously close to a flailing baby limb—and make sure they make it safely out the door. Between my own klutziness and my children, there’s no way that one of them wouldn’t have ended up with burns, and our house would have had many more broken mugs without my trusty Zojirushi around. The locking mechanism keeps those curious child paws from getting into it but is simple enough that I can undo it and flip the lid with one hand if the other is occupied. Maybe I remember to pick the coffee back up right after I set it down, but usually I’ve wandered off. Twenty minutes or two hours later, I’ll remember, and—unlike in a standard mug—my coffee is the same temperature as I left it: still almost unpleasantly hot.

The only problem I have with the Zojirushi mug is that sometimes it keeps the coffee too hot, and I have to leave the lid open for a few minutes when I first start to drink to let it cool off. Still, that’s a much better problem to have than the other way around.

How this cult classic coffee thermos became a total game changer

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