General description This set of 3 countersink drill bits is crafted from high-quality HSS stainless steel and features a titanium coating to minimize friction and heat during use. Designed for versatility, these drill bits can effectively drill holes in various materials such as steel, brass, wood, and plastic. The unique step design allows for precise drilling of different sizes, eliminating the need for multiple drill bits. Technical specifications Material: HSS stainless steel with titanium coating Sizes: 4-12mm, 4-20mm, 4-32mm Length of drill bits: 4-12mm (Approx. 6.7cm / 2.64"), 4-20mm (Approx. 7.4cm / 2.91"), 4-32mm (Approx. 10.2cm / 4.02") Recommended speed: 250-400 RPM/min Suitable for materials with hardness of 25° or less and thickness less than 5mm Usage No pilot holes or pre-drilling required Automatically deburrs holes as you drill Ideal for thin metals, aluminum, copper, brass, fiberglass, and PVC Always wear protective glasses when using tools Other information Product