Hyamass 60Pcs Drill Bit Set, 1.0-3.5mm 4341 HSS Micro Drill Bits for Hardened Metal, Stainless Steel, Cast Iron, Wood & Plastic, All-Purpose Drill Set for Tools

【Advanced Heat Management System】 Our drill bit set features optimized flutes that actively clear chips/debris, reducing friction by 40% for cooler drilling. Ideal for metal drill bits operating on steel, alloy, or cast iron, ensuring faster penetration without overheating damage. 【Industrial-Grade HSS Construction】 Forged from premium high-speed steel (HRC 63-65), these metal drill bits for steel deliver unmatched hardness and wear resistance, providing long-term rust protection even in humid environments. 【Multi-Material Mastery】 Precision-ground drill bits sets tackle 5mm thick materials effortlessly – from soft metals (aluminum/copper) to hard plastics and hardwood. NOT for masonry/glass. Perfect balance between 135° split-point accuracy and shock-resistant toughness. 【Professional Surface Finish】 Laser-calibrated cutting edges paired with full-body polishing ensure burr-free holes in metal drill bit applications. The reduced surface friction enables smoother starts on curved surfaces and sheet metals. 【Ultimate DIY Versatility】 This 60-piece metal drill bit set for steel covers 1.0mm-3.5mm sizes for diverse projects – automotive repairs, furniture crafting, or HVAC installations