This Bosch holesaw set for plumbers is made up 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 19, 22, 29, 38, 44 and 57 mm holesaws plus, two standard adaptors covering 19-29mm and 38-57mm diameters.