You know those people who make traveling with babies look serene and effortless? I was not one of those people. As a new mom to two infants at once, I spent much of the first year of my twins’ life simply trying to survive — traveling with them was a next-level aspiration that would have to wait until we all got our bearings.

Eventually, we got there. After the baby phase, we were finally ready to get out on the road as a family. But one of the major obstacles we still faced was the problem of safe ground transportation. Either we had to travel with bulky car seats or we were limited to the type of cloistered resort that would supply them at all times, from the moment of airport pickup. Was there some other solution I was missing?

During one multigenerational trip in Maui, I finally figured out what it was. My then four-year-old daughter made a new Canadian friend at the resort and this girl’s family kept leaving the property for more adventurous meals and excursions via Uber. How were they doing this? The Mifold booster seat, her mom explained.

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Mifold bills itself as “the world’s most compact backless booster,” and it’s easy to see why. It’s approximately the size of a paperback book and fits in my purse or into my kids’ backpacks with plenty of room to spare. And (for the triplets parents out there, bless your hearts) it’s narrow enough to fit three in a row across the back seat of most cars. It works by pulling down on the adult seat belt to adapt it so it fits a kid safely and securely.

As soon as I got home from that trip, I ordered a pair of the reasonably priced gadgets for my twins — and have never looked back. We have since tossed them in carry-ons and used them in rideshares, taxis, and rental cars all around the world; they’ve flown with us from Mexico to Marrakech, from Bora Bora to Barcelona.

To buy: walmart.com, $40

Does it sound too good to be true? I wondered that too, but Mifold is actually regulated for use in every US state, as well as by universally accepted global car booster seat regulations in the European Union and Canada. (Note that it’s not available for sale or use in Australia, which has its own set of safety standards.)

That said, there are a few caveats. Mainly, the seat is designed for kids age 4 and up, who weigh at least 40 pounds (up to 100 pounds), and who are at least 40 inches tall (up to 59 inches). So this won’t substitute for a forward-facing infant car seat, and it’s not regulated for babies or smaller toddlers. But it’s something parents will want to bookmark for when the time is right. What’s more, Mifold is compact but dense — it weighs about 10 pounds. So plan for that added weight if not much additional bulk.

Last, my kids tell me it’s not the most comfortable thing to sit on for long stretches. And even though this model is called Comfort because of its extra padding, I’d say their assessment is feasible given its rigidity. I’d estimate you could cushion it with a sweater, say. Or just encourage the kids to buck up and tolerate a minimally inconvenienced backside — it’s a small price to pay for their travel adventures.

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This summer, my kids will turn 8. And on that milestone birthday, they will no longer be legally required to use booster seats at all. While the upcoming transition comes as a logistical relief, it’s also bittersweet: It signals the end of the days when our travel boosters took us around the globe with our wide-eyed little ones, a great pleasure and privilege I suspect none of us will ever forget.

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