There's got to be a catch. . .
 

That's pretty sweet.

You that worried about flats that you need a C shaped inner tube? Might not be bad if you just use it as a spare – at least you wouldn’t need a wrench to get the wheel off. Still, I don’t think I’ll be buying one.

I use a repair kit when I get flats rather than carrying a spare tube, You can fix punctures without taking the wheel off using the same method. I guess to remove the old tube they have to cut it in half. I think I'd rather just patch and reuse.

Specialized made that in the late 90's....called it the "dirt worm"...didn't catch on obviously.

Could be good for bikes with Sturmey Archer hubs, those can be a ***** to fix a flat on ....

Exactly. There are instances where this would come in really handy - like on a bike with fenders and rear-facing dropouts...ahem....track ends.

Its clearly a bmx product. BMX ridign causes a lot of pinch flats, especially if you land short on a curb or stair, and with a lot of street riding pegs are on at least one side making wheels harder to get off.

not sure if you could apply something like that to a tubeless tire and just not get flats for the life of your tire. I'm not sure what kind of pressure limitations it has or how much weight it would add