... 5/8"(168mm),7 1/2"(190mm), 7 7/8"(200mm),8 1/2"(215.9mm), 9 1/2"(241mm),9 5/8"(245mm), 11 ... 5/8"(295mm),12 1/4"(311mm), 13 ... 5/8"(346mm),14 3/4"(374mm), 15 1 ... different tooth shape, tooth density and tooth exposure height. 17 1/2" milled tooth tricone bits for well drilling mine drilling