This Bosch holesaw set for electricians is made from the HSS bi-metal holesaws. Featuring the vario tooth strip, it makes for fast and precise cutting. The 8% cobalt in alloy makes for a longer lifetime. A range of all popular metric sizes. Set includes 20, 25, 32, 38, 51 and 64mm holesaws plus, two standard adaptors covering 32-64mm and 20-25mm diameters.