Details:- Repairs damaged threads without undercutting good threads.- For quick repairs of damaged threads on bolts and studs.- Sizes: 1/4″-20, 5/16″-18, 3/8″-16, 7/16″-14, 1/2″-13, 9/16″-12, 5/8″-11 – Packed in a reusable clamshell package