Durable stainless steel construction offers strong, long lasting performance and rust resistance for reliable use over time. Efficient and accurate square hole design improves drilling speed and hole quality. The square hole bit design helps you produce cleaner squares with less effort and works with most drills. Quick, tool attachment with a skid mounted design allows you to attach or remove the adapter from the drill tip in seconds, without additional tools. Very practical and versatile. Compatible with both hand drill accessories and bench drill accessories. Supports drill bits with a diameter of 38 mm to 55 mm (1.5 to 2.2 inches). Practical applications: ideal for fast square hole drilling in metal workpieces such as fabrication frames or joints; useful on site with a hand drill when a bench drill is not available; suitable for piercing related projects or frames requiring square holes. Compatibility and performance: designed to fit most drills and deliver consistent results across a range of drill bit sizes within the specified range.