HSS Spiral Grooved Step Cone Drill Drills Bit 4mm - 12mm/20mm/32mm Hole Cut
100% brand new and high quality Drop forged, heat treated, high speed steel, fully polish Take the guessing out of drilling by supplying the proper depth for you Use for home and industrial Specification: Material: High speed steel Color: Golden Quantity:1 Set (3Pcs) Dimension: #1: 4mm to 12mm 9 Steps (4mm,5mm,6mm,7mm,8mm,9mm,10mm,11mm,12mm),7cm(L) #2: 4mm to 20mm 9 Steps (4mm,6mm,8mm,10mm,12mm,14mm,16mm,18mm,20mm),7cm(L) #3: 4mm to 32mm 15 Steps (4mm,6mm,8mm,10mm,12mm,14mm,16mm,18mm,20mm,22mm,24mm,26mm,28mm,30mm,32mm),10cm(L) Note: When drill the hardness and larger diameter hole, must cooling the bit with cool water, recommend the drilling rate for 120-240 is suitable for processing 6 mm and below plate, the bits are high speed steel material, drilling rate are 120/minute, expanding to more than 20 mm hole, drilling rate shall not be higher than 400 RPM and used water cooling. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package includes: 3 X Hex Spiral Grooved Step Drill Set