1.Certification:ISO&API 2.Size range from 3 3/4" to 26" 3. ... of compacts and decreasing the breakage rate by using the tungsten carbide compact of high strength and toughness.b. Improving the ... , 627G, 637G9 1/2241.3437G, 517G, 537G, 547G, 617G9 5/8244.5437G, 517G, 537G, 547G, 617G9 7/8250.8437G, 517G ... 537G, 617G, 627G, 637G 7 7/8" Kingdream HA737G tungsten carbide tricone drill bit /three cone bit