8 1/2" Tricone Drill Bits 1-Rubber mealing 2-API or ISO 9001:2008 3- ... -171/2( inch) TypeTricone bits, Steel tooth bits, PDC bits Applicable water well, oil field, construction, geothermal, directional boring, and underground foundation work Formation ... 1/2444.5517G, 537G, 617G, 627G, 637G roller cone rock bits