T38 retrac button bits drill bit hard rock

T38 retrac button bits, China button bits manufacturers, T38 64mm button bits, T38 70mm button bits, T38 76mm button bits, T38 89mm button bits. 1) Diameter: 64mm, 70mm, 76mm, 89mm Button Bits. 2) Material: 45CrNiMoV,YK05. 3) Advanced heat treatment technology. 4) Variety carbide tips suitable for different rock formations. 5) Thread connection: H25, R22, R25, R28, R32, R38, T38, T45, T51, ST58/ED68, GT60. 1. Standard body & flat face 2. Standard body & drop center 3. Retrac