General description This HSS 3 piece step drill set features spiral groove peeling drills designed for metal, wood, plastic, and more. The set includes drill sizes of 4-12mm, 4-20mm, and 4-32mm, allowing you to replace 19 individual drills with just one tool. The taper tip with a stair profile enables auto-start drilling without the need for pilot holes, making it efficient and user-friendly. Technical specifications Sizes: 4-12mm, 4-20mm, 4-32mm Material: High-speed steel (4241 HSS) with titanium coating Length: 7 cm for 4-12mm and 4-20mm; 10 cm for 4-32mm Number of steps: 9 steps for 4-12mm and 4-20mm; 15 steps for 4-32mm Color: Golden Usage This drill set is ideal for cutting holes in various materials, including: Steel Sheet metal Wood Plastic Thin iron Aluminum alloy Insulation board PVC film Other information Automatically deburrs holes as you drill Good chip evacuation and even cutting Reduces friction for smoother operation Scope of delivery: 1 x twist drill 4-12mm, 1 x spiral