... ,121,227,417,437,517,547,617,637Applicable forPetroleum & gas, water well and mining Bearingmetal bearing(HJ), rubber bearing(HA)Advantagehigh quality with ... reasonable price because of used productFormationsoft and medium formation, hard formationButton bitsmall tooth, big tooth, conical inserts ... : API steel tooth tricone bits 7-7/8HA116 FOR OIL AND WATER WELL DRILLING