... Drilling Tools, Threaded Extension Drilling Tools, Downhole Tools, Tricone Drilling tools and Coal Mining Tools. Main products:Tapered button bits (28mm, ... integral. Rod 19mm, 22mm; Shank hex. 19mm, 22mm)Thread Button Bits (33mm, 35mm, 45mm ,51mm,57mm,64mm,70mm,76mm, 89mm ... , 35mm, 38mm; Round 32mm, 38mm, 45mm, 51mm)Retrac Button bits with different Thread different diameters. (51mm, 64mm,70mm,76mm,89mm ...