The step drill is made of HSS steel and is extremely durable when using coolant. The clearly visible and permanent diameter markings in both spiral flutes are laser-etched. The HSS step drill creates smooth and burr-free holes with various diameters. It is ideal for drilling and enlarging holes. Center punching is not necessary, as the cross-ground tip facilitates the initial drilling. The CNC-milled spiral flute optimally removes chips and allows for even drilling. Axial and radial relief grinding ensures maximum cutting performance and absolutely smooth results. The step drill is suitable for thin materials made of non-ferrous metals, stainless steel, and plastic, as well as steel sheets and plastic panels. Specifications: HSS-TiN, step diameter (range) mm: 4-20, step height mm: 4, total length mm: 70.5, shank diameter inches: 1/4.