- Versatile size range: a progressive step drill bit can drill multiple hole sizes with one tool, allowing a wide range of diameters without swapping bits. - No center punch required and improved durability: less prone to breakage than ordinary twist drills, making it suitable for on-site work with differing specifications. - Multi-function hole processing: deburs, chamfers, starts holes, and can open and enlarge elliptical holes; these functions are not available with standard twist drills. - Stable and clean results: reduced vibration and wandering yield neat holes with smooth edges, without the need for additional grain or finishing after drilling. - Practical compatibility and performance: designed for on-site construction and versatile hole sizing, compatible with common materials encountered in field work. Use scenarios: - Drilling and finishing holes for electrical enclosures, control panels, and wiring pass-throughs. - On-site metal sheet fabrication where varying hole sizes and edge finishing are required. - DIY projects requiring deburring, chamfering, or enlarging elliptical holes for components or fittings.