Abracs Cobalt Holesaw is for use by professional trades people on a wide range of applications. Bi metal construction with 8% Cobalt for extreme strength, durability and performance. Abracs Holesaws are manufactured with high speed variable pitch teeth for fast and clean cutting. 17pc kit contains 1 x 16mm, 1 x 20mm, 1 x 22mm, 1 x 25mm, 1 x 32mm, 1 x 38mm, 1 x 44mm, 1 x 51mm, 1 x 57mm, 1 x 64mm, 1 x 76mm, 1 x A1 arbor, 1 x A2 arbor, 2 x HSS pilot drill bits, 1 x ejection spring, 1 x extension bar