HARFINGTON 10pcs Jobber Drill Bits 3.5mm (9/64") Nitride Coated High Speed Steel (HSS) 4241 Twist Drill Bits for Stainless Steel Copper Aluminum Alloy Metal Wood Plastic, Black - hta231228hh000210

• Size - Cutting edge diameter: 3.5mm / 9/64". round shank diameter: 3.5mm / 9/64". cutting edge length: 43mm / 1.69". overall length: 70mm / 2.76". split point: 135 degree (Fast cutting point penetrates quickly with less pressure and prevents walking on metal surfaces.) Material - 4241 high-speed steel provides excellent hardness, high strength, wear resistance and good heat resistance. This helps ensure efficient, consistent drilling performance, and prevent overheating and extending the life of the drill bit. Features - Black nitride coating can improve hardness, increase wear resistance and prolong its life. The nitride coating also reduces friction in the drilling process, resulting in smoother and faster drilling performance. Applications - Drill clean and accurate holes in stainless steel, cast iron, carbon steel, aluminum alloy, copper, and brass, wood and plastic. Large spiral grooves facilitate the export of metal chips, saving time an effort. NOT suitable for tiles, concrete, walls, stones. Note - Used with handheld drills, drilling machines, bench drills, machining centers, CNC lathes. Use an appropriate lubricant to reduce friction and heat build-up. Make sure the drill bit is tightened securely, and keep the drill bit perpendicular to the work surface.