EXACT HSS 3 Piece Cone Cutter Drill Set This exceptional cone cutting set from EXACT is made from HSS for high-performance, offering a range of hole diameters, giving you maximum versatility. Capable of cutting holes from 3 mm to 30.5 mm through three different cone cutters. These High-Speed Steel (HSS) cutters are constructed from a single piece of high-speed steel, thus reducing breaking and blunting under heat or stress. The tapered design makes it easier to enlarge holes if requirements change for example. Typical Applications HSS bits can be are suitable for use on steel sheets and non-ferrous metals, which include aluminium, copper, brass, zinc and iron. It can be used for drilling applications involving plastic and wood. Features and Benefits Self-centring drilling action reduces drill walking No pilot hole required easily enlarges existing holes Capable of cutting holes from 3 mm to 30.5 mm diameters Ideal for use with most power drills Supplied in a moulded Plastic box FAQ's Q. What is the difference between a Cone Cutter and Step Drill Bit? A. A cone cutter is a smooth sided bit that can make any sized hole, on a variety of materials. A step cutter has parallel measurements up the cone, gradually getting bigger. These are great if you need to cut sized holes with reasonable accuracy. These bits are also capable of cutting through various materials.