Tooth configuration optimised for the fast cutting of sheet steel - Cuts sheet steel faster than standard hole saws - 8 teeth per inch for a smoother cutting action - Cleaner holes with no burring - Premium grade 8% Cobalt Alloy Steel construction for an extended working life - Slimline design reduces frictional heat build up and prevents tooth burn out - Flared shoulders prevent overdrilling - Avoids damaging inner components of electrical cabinets and junction boxes - Compatible with impact drills - E6.3 Drive System - Contents: 20, 25 & 32 mm