... quality/Competitive price 5.Bright finished Step drill with spiral flute1.) Step drill bits 2.) Spiral ... .4-12mm4,5,6,7,8,9,10,11,12mm65mm94-22mm4,6,8,10,12,14,16,18, ... 20,22mm80mm104-32mm4,6,8,10,12, ... 14,16,18,20,22,24,26,28,30,32mm105mm156-38mm6,9,13,16 ... 37,38,39,40mm105mm1610-20mm10,11,12,13,14,15,16,17,18,19,20mm88mm11 Step drill with spiral flute