One of my biggest goals right now is to try every insulin pump on the market. I want to be fluent in all the “languages” of diabetes tech so I can better inform you, and compare the systems fairly. Every pump has its own personality—its quirks, its strengths, and its frustrations—and you don’t really know them until you’ve lived with them.

That’s what brought me to the Tandem Mobi. I’ve been using Omnipod for nearly four years—I’ve tried both DIY Loop and the Omnipod 5 algorithm. After years fully immersed in the tubeless lifestyle, it was time to see how the smallest hybrid closed-loop tubed pump in the U.S. fit into my life. The decision was made easier by Tandem’s 90-day return policy—a comfort when you’re about to swap out such a critical piece of your diabetes toolkit. I ended up using that policy after testing Mobi for just under three months, but not before getting a full understanding of what it’s like to wear and rely on it. Oh, and keep in mind that some DMEs only allow a 30-day return policy.

Unboxing the Mobi felt a little like opening a sleek new gadget—except this one was about to take over one of the most critical jobs in my life: my pancreas. Inside, you’ll find a reusable pump body (black, tiny, but solid in the hand), disposable cartridges that you fill with insulin, infusion sets with the tube length of your choosing, and a 10-pack of adhesive patches.

There are two sizes for tubing: the 23-inch set gives you the flexibility to slip the pump into a pocket or clip it to your waistband and the 5-inch set keeps Mobi close to your infusion site where you can adhere the pump to your skin with a patch.

The adhesive patches were one part I wasn’t thrilled about. Compared to the smaller footprint of an Omnipod, these felt bigger and looked more medical to me. I eventually started experimenting with alternatives, including diamond-shaped patches from the Kaleido pump in Europe, which hide the adhesive behind the pump itself—I was able to snag some of these at ATTD. They looked better, but won’t always keep the pump on you during intense cardio.