Professional Quality: The bi-metal hole saw is made of premium M42 high-speed steel, providing strength and abrasion resistance. The high-speed steel teeth are heat-treated to achieve high hardness (65HRC), ensuring durability and reusability. Chip removal design allows for efficient evacuation of chips, improving performance when removing cylindrical material from holes. Clean edge design enables smooth and effortless cutting. The spring mechanism automatically ejects the center washer after drilling. Compatible with standard adapters for use in drills with SDS-plus or hexagonal chucks. Suitable for use in wood, plastic, aluminum, non-ferrous metals, copper, plasterboard, and similar materials. Works with magnetic drills, hammer drills, and other common drill types. Convenient and practical for professional and DIY applications.