when the Air Boss first came out I'd guess about 20 years ago now they were called Iatco segmented tires , and the name changed to Air Boss while we were using them , we guinnea pigged a few sets in our rental fleet , they do work well in certain applications and were terribble in others , running Grousser tracks on top of them was the strong point , concrete demolision and working in dirt without tracks was their weak points we got them thru a company called World Tire in Atlanta , Tony Brown was the sales rep , not sure if they are still around ------------but anyway this is what learned about replacing pads on them , they use to be pretty expensive , like $18 per pad 20 years ago , and you can't just put a few new pads in place of broken one as you would get a lump from the new pad being bigger than the used ones , so what we did was to save all the usable pads left from a wheel rebuild and fit them into the spots that needed a pad replaced -----------------finding usable used pads I would think is going to be tuff