Onepiece spiral step drill bit — 9-step cutting for fast, clean holes Key benefits Faster, more efficient drilling: the one-piece spiral step design cuts progressively through material so you can enlarge holes in a single tool instead of swapping multiple bits. Precise, repeatable hole sizes: use the stepped profile to stop at the exact diameter you need. Versatile for common materials: designed for cutting holes in sheet metal, steel, and wood. Main features Onepiece spiral construction for consistent cutting and heat distribution. 9 stepped diameters in a single bit for multi-size capability. Two available size ranges: 9-step 4 mm to 12 mm, or 9-step 4 mm to 20 mm — choose the set that matches your project needs. Ideal for creating clean holes quickly in thin to moderate-thickness materials commonly found in metal and woodworking tasks. Practical applications Electrical and HVAC work: punch precisely sized holes in sheet metal panels and junction boxes for conduit, fittings, or cable entry. Automotive and metal fabrication: enlarge or deburr holes in vehicle body panels and steel brackets without repeatedly changing bits. Woodworking and installation: create stepped holes or enlarge pilot holes in cabinetry, trim, and furniture where multiple diameters are needed. Why customers choose this bit Saves time: multiple hole sizes in one tool reduce bit changes and setup time. Controlled results: stepped profile helps you stop at the exact diameter for a snug fit of fasteners, bushings, or fittings. Practical and compact: replaces several individual drill bits with one durable step bit. Usage notes Designed for drilling holes in sheet metal, steel, and wood; use appropriate speed and cutting technique for each material. Available in two 9-step ranges: 4–12 mm or 4–20 mm. Select the range that matches the hole sizes you need. This Onepiece spiral step drill bit delivers an efficient, practical solution for repeated hole-making tasks across metal and wood applications, with predictable stepped sizing and faster operation than changing many single-diameter bits.