... 17 1/2" tricone drill bit : size from 60mm to 26 inch,metal sealed and Elastomer sealed,have new and old in stock ... .export to many countries,have a good feedback. 1. Metal-face sealed bearing Tricone ... AvailableSize: 2 3/8",3",3 5/8:",3 7/8",4",4 1/2",4 5/8",4 3/4",6",6 1/2",7 1/2",8 1/2",9 1/2",9 5 ...