Purchased these tire repair plugs for my motorcycle. Lucky for me I was at home when I first used them.Basically, the sticky plug did not insert into the puncture far enough to prevent air from leaking out when the tire was inflated. The metal point went in after some hard pushing and turning. Seemed that the hole made by the roofing nail was smaller than the tool diameter.I tried 3 times using new plugs and each time following the directions. Finally, I was able to push the third plug in further than the tool had, enough to stop air from leaking.Now going to have the shop put a patch on the inside of the tire because I do not trust the plug.I have had better luck with the plugs you fold in half and center on the tool then insert, twist and pull the tool out, leaving the plug in the tire.