1.Sizes rang from 3 7/8" to 26" 2.Covers almost all ... Tricone BitsTCI tricone bit 1.Sizes rang from 3 7/8" to 26" 2.Covers almost all IADC code ... 4517G, 537G, 617G, 637G6 1/2165.1517G, 537G7 7/8200.0517G, 527G, 547G, 617G, 627G, 637G8 1 ... .3437G, 517G, 537G, 547G, 617G9 5/8244.5437G, 517G, 537G, 547G, 617G9 7/8250.8437G, 517G, 537G, 547G, ... 637G17 1/2444.5517G, 537G, 617G, 627G, 637G 5 7/8"TCI Tricone Bit