... Step drill with spiral flute1.) Step drill bits 2.) Spiral flute 3.) Step drill, bright finished 4.)HSS steel 5.) ... hole diameters can be drilled using only one tool and holes are deburred automatically by the following step.*Suitable for ... ,10,11,12mm65mm94-22mm4,6,8,10,12,14,16,18,20,22mm80mm104-32mm4,6,8,10,12,14 ... 20,22,24,26,28,30,32mm105mm156-38mm6,9,13,16,19,21,23,26,29,32,35,38mm100mm126-40mm6, ...