length : as picture show is_customized : Yes Use : Metal Drilling Material : Cobalt Steel Alloys Model Number : drill bits DIY Supplies : Woodworking Type : Twist Drill Bit : NIUXIANG Origin : Mainland China Certification : NONE About this item 5% COBALT TWIST DRILL BITS SETMade from M35 Cobalt Steel with Molybdenum and Cobalt added to form a hardened alloy, can measure up to 67 Rockwell hardness, cut faster, last longer, and last longer than normal HSS drill bits 12 times. TWIST DESIGN AND PERFORMANCEPrecise 135 SPLIT Point, Gold Oxide Surface and Round Straight Shank. Prevents walking and removes chips and particles faster. Precision fully ground to ensure smooth chip movement. PROFESSIONAL AND WIDELY USEDM35 Cobalt High Speed Steel is more suitable for hardening materials. Ideal for cutting stainless steel, steel and cast iron as well as wood, aluminum alloys and other metals. Not suitable for glass or ceramic materials. Pay attention to speed, pressure and heat control when drilling. SERVICEIf you have any problem with our metric drill bit set or are not satisfied with the product, please feel free to contact us.