Step Drill Bit, HSS Metal Countersink Drill Bit, 4pcs 4-12/20/32mm Step Drill Bit Steel Countersink Drill Bit Triangular Conical Drill with Titanium Coating Screwdriver Drilling for Steel/Wood/Brass/P

【3+1 Size】1*72mm: The scale on the drill is 4-12. 1* 72mm: 4-20. 1*102mm: 4-32. 1*72mm twist drill. The drill can process holes of different sizes

【Robust and rust-proof HSS】 Made of high-quality HSS, it cuts thin materials quickly. HSS offers extreme durability and the drills are rust-proof. At the same time, our drill is suitable for electric screwdrivers.

【Area of application】Step drill suitable for DIY, household and construction. It is very suitable for drilling holes in a variety of materials such as steel/brass/wood/plastic/thin iron plates/aluminum materials/insulation boards/PVC boards, etc. Only suitable for ordinary aluminum, iron and steel plates (thickness cannot exceed 4mm, hardness is less than 25HRC), not for stainless steel

【Twist Drill】The 4mm HSS 6542 twist drill allows you to pre-drill materials, which makes the step drill less easily damaged than ordinary step drills. Note: Oil the stepped bits before each use to maximize service life.