The BlueSpot HSS Step Drill is manufactured from high-speed steel for increased durability and cutting power. It is designed for precision drilling of holes in aluminium, brass, copper, plastic, steel and wood. The step drill features 14 steps with 2mm increments for the first few sizes and 3mm increments for larger sizes, ranging from 4mm to 42mm. It is titanium coated to reduce friction and heat during use. This product comes with a lifetime guarantee upon online registration.