... Europe Hejian Huanyu Petroleum Machinery Co., Ltd. in China.1) Product :we specializes in manufacturing:Tricone bits,steel tooth ... 8245-49080-40187.3~311.17 3/8- 12 1/4490-78480-40mediumHard Shale, Limestone, Medium/Hard Sandstone etc ... 7/8294-53980-60187.3~241.37 3/8-9 1/2539-83360-40hardSandy, Shale, Quartzite, Hard Dolomite, Hard ... 40Contact information TCI Bit 165 mm with 3 1/2" REG Pin for Hard Rock