Gustavo 2-Pack Ultralight TPU Inner Tube Bike 26/27.5/29 x 2.0-2.8 for MTB Mountain Bicycles Gravel TPU Tire 45mm French Valve Tube Replacement

I got these as a compact, lightweight backup tube for my mountain bike in case of a puncture that a plug and tubeless goop will not fix. These fit the bill nicely as they are really only mean to get you riding out of a a bad situation back to the trailhead. I have no illusions that they will last nearly as long as a "real" tube, but that's not what they're meant for. This frees up a bunch of space in my frame-mounted Dakine Gripper pack for a multitool and tire iron that wasn't available with a full-size tube.I will be honest and say that I have not actually inflated these and tried them out in a tire, but they seem well-enough constructed for their light weight and relatively cheaper price (emphasis on the "relatively", and why I have not "burned" one by actually inflating and using it; even for the cheaper price compared to something like a Tubolito, these are decidedly more expensive than a "real" tube, because of what they are meant for).So far so good!

These seem the same as the big name/other generic models you'll encounter, no issues. They hold air, they are still fragile like all TPU tubes are, but just be careful, I use baby powder when I install them new, and they are good to go. Hold air longer than latex and lighter too, and cheaper! Sold!