... 3.Suitable for medium to medium-hard formation. PDC bit, diamond bit, PDC core bit, PDC bits1. Circular arc brown, standard PDC cutters ... 65,75,94,113,133,153PDC bit,diamond bit,flat face non-coring PDC bit,PDC Concave Bit,PDC bits1.Different grades PDC ... protect gauge. Application:1.Mainly used for geological exploration and coal mining.2.Suitale for formation rock hardnessMain Available:55,60,65 ...