... 3.coal mining bits 1.We can supply all kinds of RUIZUAN brand coal mining bits, sleeves and ... resistance and long life features; The material of the steel body adopt the 42CrMo.The ... design, produce and repair all kinds of cutter drums.5.We can supply the following Bits and ... Holders:U82,U84,U85,U92,U94,U95,S120,S135,S150,U765K,U765HD,C31HD,AM511 etc. repair all kinds of ...