What this drill bit set solves Delivers clean, accurate holes in hard and abrasive metals where standard bits wander, dull quickly, or overheat. Extends tool life and maintains cutting performance on stainless steel, cast iron, aluminum alloy, copper, and other abrasive materials. Fits common and jobsite equipment so you can use the same bits across hand drills, bench drills, and lathes. Key materials and construction M35 speed steel body with carbide tips for improved wear resistance and longer cutting life. Silver finish and 135degree split point (cuttip) design to reduce walking and ensure precise hole placement. Performance and operating guidance Recommended speed range: 800–1500 RPM for hand drills, bench drills, and lathes to balance cutting efficiency and tool life. Requires water or cutting fluid cooling during operation when working with hardness materials to prevent overheating, which may cause solder joint failure. Keep exposed shank length minimal during use to reduce vibration and breakage. Design features that matter 135degree split point (cut tip) centers faster and reduces walking on tough surfaces—use a center punch or nail mark for accuracy on stainless or thick plates. Straight shank design is compatible with standard chucks. Diameter range: 3–12 mm to cover common metalworking hole sizes. Available in 2piece or 5piece configurations (3mm, 4mm, 5mm, 6mm, 8mm, 10mm, 12mm). Practical use scenarios Installing hardware and fittings: Drill accurate holes through stainless steel sink bases, brackets, and fixture plates without bit walk. Machine maintenance and fabrication: Redrill or enlarge holes in cast iron components and aluminum assemblies with controlled heat management using cutting fluid. Automotive and hobby projects: Create precise mounting holes in copper or aluminum panels for electrical, model, or modification work. Tips for results Mark the hole with a center punch before drilling to maximize the advantage of the split point. Use adequate coolant or cutting fluid and pause as needed to avoid overheating. Select proper RPM within the 800–1500 range based on material hardness and bit diameter. Secure workpiece and minimize exposed shank to reduce chatter and breakage. What you get Durable M35 HSS drill bits with carbide tips, silver finish, 135° split point, straight shank compatibility, and multiple size/set options for general metalworking tasks.