1)Model:114,117,127 2)material :high manganese steel 3)Certificated by API&ISO9001:2008 4) reasonable price Model HAT 117 HAT127 HAT137 HAT147 GA114 GA126 GA135 GA145 TypeTricone bits, Steel tooth bits, PDC bits Applicable water well, oil field, construction, geothermal, directional boring, and underground foundation work Formation sticky, soft, medium hard, hard formation Bearing rubber seal or ...