Actually it was worse than that. They were made of a mystery material- kind of a plasticky rubbery vinyl. The material simply extruded into the spoke holes until it blew out in one hole. When I changed the tube I tried to stretch the strip a bit so the torn section didn't end up over a hole. I may have been successful but I think the ragged edge of the strip may have been sharper than I thought. Cloth strips are next.