HSS Step Drill Bit Center Punch Drills Set 4-12 4-20 4-32mm Woodworking Metal Hole Cutter Cone Core Drilling Hole Tools Wood Box

[Special Note]: HRC (high breaking capacity);Our products are divided into two hardnesses, HRC62 and HRC67. The first material is HRC62 (marked as A on the picture), drilled plastic, wood, and aluminum are all right. But if you need to drill steel or iron plates, or want a longer tool life, we recommend that you choose the second material HRC67 (B-C is indicated on the picture).

[Specification]: 4 - 12mm: 5 Steps (4-6-8-10-12mm) Or 9 Steps (4-5-6-7-8-9-10-11-12mm) 4 - 20mm: 9 Steps (4-6-8-10-12-14-16-18-20mm) 4 - 32mm: 15 Steps (4-6-8-10-12-14-16-18-20-24-26-28-30-32mm)

[Advantages]: 1. Step drill is triangle round handle or hexagonal handle, prevent sliping. 2. "X" shaped openings, drilling is not easy to slip. Higher precision, more sharp, burr-free drilling. 3. The gold is titanium coating, more wear and oxidation resistance, not rust. 4. The unique step structure, a drill can drill a variety of sizes of the aperture. You can deburring, chamfering, punching elliptical hole. 5. The hardness of the workpiece below the use of 25 ° below, such as iron, aluminum, PVC board, insulation board, wood, workpiece thickness 4mm. 6. Suitable for installation in the pistol drill and bench drill.