They worked at first taking the first bite or two with tire spoons but soon became tiresome. The edge/crease on them is very shallow and they don't fit the rim perfectly (at least for me in the Himalayas) so I didn't even want to use them. In order for them to sit well, you have to press them into the rim with a lot of force, then they get stuck on the wheel when you pry open the tire with them. To be honest I would only use them if I had really good wheels. I took care of it, but in the end I didn't want to use it.