For repair of damaged internal threads on nuts. Chase out damaged threads and remove nicks and burrs without undercutting good threads. Use with standard wrench and light oil. Not for hardened threads.
Sizes:1/4''-28, 5/16''-24, 3/8''-24, 7/16''-20, 1/2''-20, 9/16''-18.
Packed in a reusable clamshell package.