The Faithfull Plumber's Holesaw Kit contains the 6 most frequently used plumber's holesaw sizes. These high speed steel bi-metal saws have specially hardened variable pitch teeth for fast smooth cutting. Bi-metal saws offer increased safety as they will not shatter under load. These holesaws are used to cut perfect holes in a wide variety of materials including wood, chipboard, plywood, non laminated plastics, plasterboard & non-ferrous metals. Suitable for use in most variable speed power drills. Supplied in a sturdy fabric storage case & contains the following: 6 x Varipitch Holesaws: 19, 22, 29, 38, 44 & 57mm 1 x 3/8in Hexagon Arbor for Holesaws 14-30mm 1 x 7/16in Hexagon Arbor for Holesaws 32-152mm 1 x Arbor Adaptor