... Quality products & good service 4. Good feedback of clients 17 1/2" tricone drill bit : size from 60mm to ... metal sealed and Elastomer sealed,have new and old in stock.export to many countries,have a good feedback ... 2",9 5/8",9 7/8",12 1/4",17 1/2", etc. IADC Code:4-- Series, 5 ... 8",9 7/8",12 1/4",14 3/4",17 1/2", etc. IADC Code:4-- Series, 5 ... /8",12 1/4",15",15 1/2",17 1/2", etc. IADC Code:5-- Series,6 ...