STEP DRILL 4-20MM-1PC

The MILW Step Drill Bit 4‑20 mm #48899320 is a high‑precision, professional step drill designed to drill and enlarge holes in a variety of materials with ease and control. With a multi‑step geometry, this bit lets you progress from 4 mm up to 20 mm in one tool. Its Rapid Strike tip reduces walking and ensures fast, accurate starts. Made from high-speed steel and coated in black oxide for corrosion resistance, it is built for durability. The 3-flat shank prevents slipping in the chuck and ensures strong torque transfer. Laser-etched size markings help you see which step you're on. Ideal for use in sheet metal, non-ferrous metals, plastics, and more.

Features & Specifications

• Product Code / SKU: 48899320

• Type: Step Drill Bit (Metric)

• Diameter Range / Steps: 4 mm to 20 mm over 9 steps

• Overall Length: 65 mm

• Material: High Speed Steel

• Coating / Finish: Black oxide for corrosion resistance

• Tip: Rapid Strike tip for accurate starts

• Shank: 3‑flat shank, 8 mm wide

• Application Materials: Ferrous & non-ferrous metals, stainless steel, aluminum, brass, copper, plastic

• Maximum Workpiece Thickness: Approx. 4 mm (recommended)

• Markings: Laser-etched step size markings

• Anti-slip Design: 3‑flat shank to prevent chuck slipping

• Durability: Optimized geometry and coating for longer life