- Designed for use with hand drills over 550W, this set is ideal for drilling holes with a diameter greater than 14mm in materials with stainless steel hardness below 25 degrees. For optimal results, a bench drill is recommended. - Enhance your drilling efficiency by injecting water while drilling to cool the bit, which significantly extends its lifespan. The recommended drilling speed is between 250 and 400 RPM. - This 6-piece step drill bit set features HSS 4241 steel with a cobalt coating, reducing friction and ensuring cooler operation. It replaces 50 individual drill bits, saving you space and simplifying your toolkit. The two-flute design allows for faster and smoother cutting. - The large bit features a 3-sided shank while the smaller bits are equipped with a hex shank to prevent slipping in the drill chuck, providing stability and control during use. - Constructed from cobalt steel with titanium coating, these bits offer exceptional durability and maintain sharpness for many years, making them a reliable choice for various applications. - Perfect for cutting holes in a wide range of materials, including carbon steel, brass, wood, and plastic. Ideal for both professional and DIY projects, whether you're working on home repairs, crafting, or industrial tasks. - This step drill bit set combines functionality, compatibility, and superior performance, ensuring you have the right tools for any drilling job.