3Pcs HSS Spiral Flute Step Drill Bit Triangle Shank With Automatic Center Pin Punch For Hole Drill

Features Spiral groove step drill bit Titanium coating reduces friction and heat Surface nitrogen treatment increase hardness and wear resistance High speed steel Higher quality than ordinary twisted drilling and durable Can work without coolant The unique step structure the drill can drill a variety of sizes of the aperture Center Pin Punch Simple and accurate to use knurled handle prevents slipping Spring pressure can be adjusted by simply rotating the knurled top of the punch Specification Spiral groove step drill bitTypeStep drillMaterialHSSSurface treatmentNitrogen treatment increase hardness and wear resistance Shank shapeTriangular round handleQuantity1 Pc x 4 12mm Step Drill Bit1 Pc x 4 20mm Step Drill Bit1 Pc x 4 32mm Step Drill BitSizeCutting Diameter RangeLengthShank DiameterWeight4 12mmApprox 65mm 2 60 inch6mm18 5g4 20mmApprox 76mm 2 99 inch8mm47 5g4 32mmApprox 101mm 4 02 inch10mm167 6gCenter Pin PunchMaterialKnurled steel body alloy steel tipColorBlackTotal length5 inchPackage Included 1 Pc x4 12mm Step Drill Bit1 Pc x4 20mm Step Drill Bit1 Pc x4 32mm Step Drill Bit1 Pc xCenter Pin Punch1 Pc xCloth bagMore Detail