Eachine 3pcs Hss Step Drill Straight Flute/spiral Groove 3-12/4-12/4-20

Description: 3pcs HSS Step Drill Straight Flute/Spiral Groove Ladder Drill Hexagonal Shank 3-12/4-12/4-20 Introduction: Step drill,also known as multi-purpose drill with straight flute,spiral groove,single slot. White diamonds,titanium drill,colorful diamond,black diamond.Handle a round handle,triangular handle,hex shank,SDS shank. It has the functions of deburring, chamfering and elliptic hole enlargement. Don't need to use center punch, it is more durable and not easily broken compared with the ordinary twist drill. Specification: Material: High Speed Steel 4241 ( Used for the hardness of the material which is below 25 like iron borad, steel board, PVC board, Insulation board, etc.) Surface: Titanium Plated Type: Straight Flute/ Spiral Groove Handle: Hexagon Shank Scop: thin iron plate,aluminum,insulation panels,PVC panels 4mm thickness within the timber. Size Drilling Range(mm) Steps Height(mm) {Straight Flute} Height(mm) {Spiral Groove} Height of Shank(mm) Shank Diameter(mm) 3-12 3,4,5,6,7,8,9,10,11,12mm 10 78 68 24 6.3mm 4-12 4,6,8,10,12mm 5 68 73 4-20 4,6,8,10,12,14,16,18,20mm 9 73 73 Features: High speed steel material, more durable. Titanium coated to reduce friction and run cooler No need for a pilot hole, can automatically deburr holes as you drill. Special step stucture, can drill different size holes, 1 step drill can be used as 1 box of drill bit. Working with water cooling, can effectively extend the service life of bit, drilling speed 250--400 recommended. Widely used to cut holes in a variety of material like steel, wood, thin iron, aluminum alloy, insulation boards, PVC sheet,ect. Package included: 1x 3-12 Step Drill 1x 4-12 Step Drill 1x 4-20 Step Drill Straight Flute: Spiral Groove: