... steel and tungsten carbide tips via forging,welding and heat treatment to make the Product caol mining bit, mining toolsAbundant Technical ... first,Reputaion first",and sincerely wish to cooperate with friends from domestic and overseas in technical coordination ... and drawings.We can also supply the following Bits and Holders:U82,U84,U85,U92,U95,S120,S150,U765K,U765HD,C31HD,AM511 etc. coal mining ...