... 3.Material:Carbon Steel 4.Competitive price Type:Drill Bit Description of the 8 3/8" Kingdream TCI Tricone ... and high drillability such as shale, clay, soft limestone, rock salt, gypsum,etcPayment termsL/C, T/T, Western ... Providing the bearing system with good lubrication, extending the bit life and ensuring the normal work of the O ... 8 3/8" Kingdream HA 447G TCI Tricone rock drill bit/three cone ...