... ). High quality and competitive price 2). many years experience in well drilling equipments Available sizes:4 5/8"(118mm), 5 7 ... steel, carbideDelivery termsBy sea or by airapplicationPetroleum and gas, water well, mining and tectonic industries, oil field, construction, geothermal, directional boring ... exposure height. 17 1/2" milled tooth tricone bits for well drilling mine drilling