The C.A.M.P. USA Pro Nut stopper set includes 7 sizes that will fit in cracks from 7mm wide to 33mm wide. Nuts feature a half-moon shape for accurate, secure placements. Grooves on the convex sides of the nuts are designed to ease extraction. Anodized colors help you quickly identify which nut you need. Buy the 7-piece set and save over individual-piece prices.