Trend HSS Bi-Metal 8% Cobalt Holesaw 7 Piece Plumbing Set, high-performance, trade-rated holesaws with variable pitch for a smooth, fast cutting action in a variety of materials up to 38mm thick. Contains common sizes for a variety of plumbing tasks. Ideal for cutting holes for water and waste pipes in timber, MFC, plastics, steel, stainless steel, plasterboard board and non-ferrous metals.