If you follow the directions exactly and make sure the part is firm then it works like its suppose to. My review on these are mixed! I think I would consider that a failure. It is backwards. That size was too perfect. They do start out a little firm but within a couple of wearings, they were exactly what I wanted. PROBLEM SOLVED! Definitely worth the purchase. 5-7 size, and am glad I did because after a month-ish of wearing them regularly, theyre now perfect. "Old Times" brings an old cop and an old hero out of retirement.