1. VERSATILE DRILL BIT SET: This high performance drill bit with 10mm/12.7mm shank is designed for multiple materials including 45 gauge steel, 1mm stainless steel, chrome steel, iron, copper, aluminum alloy, plastic, and wood. Available in sizes ranging from 12mm to 35mm to meet various drilling needs. 2. PRECISION ENGINEERED DESIGN: Featuring a 118° double relief angle that delivers faster drilling speed and exceptional accuracy. The optimized cutting edge provides clean holes while reducing effort and fatigue during extended use. 3. EFFICIENT CHIP REMOVAL: Advanced flute design allows for fast and efficient chip evacuation, preventing bit clogging and overheating. This improves drilling performance and extends the life of your drill bit while maintaining smooth operation. 4. SECURE GRIP HANDLE: The specially designed handle ensures stable clamping and fastening during operation. Bits 12 21.5mm feature a 10mm shank diameter, while larger sizes come with a robust 12.7mm (1/2 inch) shank for compatibility with standard power drills.