Drilling Roller Bit Milled Tooth 490 mm IADC 121 Tricone Roller Bit 19-1/4 Steel Tooth. API 7-1 & ISO9001 Certified: Strictly complies with API Spec7-1 and ISO9001 quality management standards. 30 Years Manufacturing Experience: Established in 1990 with extensive expertise in drill bit production. OEM & Customization Support: Accepts all OEM orders and offers customized colors and seals. Premium Steel Tooth Design: Milled tooth tricone bit made from Cobalt Steel Alloys and 4145h. Wide Size Range Availability: Covers all sizes from 2' to 26' for various drilling needs. Advanced Production Equipment: Equipped with 5-axis machining centers and NC sintering furnaces. Global Export Capability: Products exported to North America, Middle East, and Russia.