ROKTOOLS Step Drill Bit Set 3-12mm 4-12mm 4-20mm HSS Straight Flute Titanium Coated Wood Metal Hole Cutter Core Drill Bit Set

Hexagonal Shank

The Cutters Come in the Following Sizes:
3-12mm(3mm,4mm,5mm,6mm,7mm,8mm,9mm,10mm,11mm,12mm) 10 Steps
4-12mm: (4mm, 6mm, 8mm, 10mm, 12mm) 5 Steps
4-20mm:( 4mm, 6mm, 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm)9 Steps

Suitable material: Workpieces with general hardness, such as wood, plastic, PVC plate, iron plate, plate thickness within 3MM. Please note that stainless steel and spring steel are not applicable. Not for quenching. (Water injection cooling while working, it can effectively extend the service life of the drill bit, especially in the case of continuous drilling)