Awesome!

I weighed these and compared them to the rubber tubes I took out. They were exactly 1lb lighter per tube. When I installed them I heard air leaking which concerned me at first. However, they take a minute to expand and it was air coming from the cavity between the tube and the rim-tape. They roll much faster and have maintained the pressure at which I installed them three weeks ago. Excellent tubes.

I haven’t actually put these in a tire yet, but I carry them as spares. They give me a lot more confidence than the cheap internet ones that didn’t even hold air when I inflated them to shape outside the tire. These ones hold air, and seem high quality

Put some kms on these TPU tubes in my 4” dillingers. After at least 250km, they are holding up without issue, with varying pressure (4-8 PSI). Lighter too!

Solve leaking problems

Jay shipped my light quickly, and it arrived a couple days later. The light itself is great - can't think of anything else I would need.

Well, dropping 300-350g per wheel makes your fatbike ride more like a gravel bike and less like a dump truck. Spin up is noticeably faster. Tire compliance over postholes is smoother. Still running same 5psi. Currently in the "testing phase" before going out in the deep woods on long treks. One tube is holding air great, the other lost a bit more overnight than I would hope for. Will check back on that, early days. The stem is not metal like a butyl tube, but a plastic material with the normal valve core in it. Assume that the metal doesn't reliably bond to TPU like it does to butyl. And there is no "locking nut" like at the stem of a metal butyl tube to screw down against the rim surface. Thought that was a bit oddly different, but it works just fine. The reported weight is as stated for the tubes. Been using them down to -20C. So far, it's all positives. Note that if your tire bead won't "pop out" Ottalaus says soapy water is fine (in moderation) to lubricate the tire/rim interface and won't adversely effect the TPU. I had more trouble with the beading popping out fully, for some reason, than I've had with butyl tubes. The TPU material is pretty thin (of course), so I wiped out the tire and cleaned the rim contact area thoroughly (then even used shop air to blow out any remaining particles) before install, so there would be no grit to abrade the TPU. Likely overkill, but since they do cost more, I thought some care was warranted. Service/answering questions from Ottalaus has been top notch. Pretty pleased if they turn out to be durable. And, as I run diff tires in the summer, no sealant mess to deal with.

Jay is awesome to deal with and always goes the extra mile with support! He is also on point with great suggestions for upgrades. Ottalaus also has all top notch products!

Faster than expected shipping. The Fatty Stipper install went very well and the air is holding with some sealant. I almost ruined one by tightening the valve before it was all the way through the strip but that was my error. I should have set the valves through the strip before placing on the rim. It would have been an easier installation than it already was. A must for Giant Yukon fat bike rims.

Easy to install, holding up well, no air loss or anything in the first month of riding. So much lighter than the original butyl tubes.

Outstanding service, would definitely use them again.

Looks great, waiting on a build with it!

communication with seller was great as 100% accurate with items..above and beyond transaction

I had an issue with a product I'd ordered from Ottalaus. Jay was quick to offer and send a replacement before I'd even returned the original product. He had me riding asap.