My daughter and I built a set of ISO 520 rims for her 24" mid-80's vintage Schwinn/Giant Sprint road frame. We were going to use another brands tiny knobby tires but they proved difficult to source, everybody seems to sell but none had the size we wanted. This was our second choice and I was a little skeptical when these came out of the box because they were thin and small and narrow but after getting them on the bike they really are well made and "feel" just right, grippy but low friction, have not yet tried in the wet. They need air, don't be afraid to put a lot in to avoid pinching. BTW, no one seems to have a 1" ISO 520 tube, we used the 1.125" tube sold here at tree fort and all was well, the tires are made in Japan.