Professional quality: the bi-metal hole saw is made of high quality M42 high-speed steel, which is robust and resistant to abrasion. High-speed steel teeth are heat-treated, high hardness (65HRC), reusable and durable. Chip elimination designPre-drilled holes have a favorable impact on chip evacuation to improve the speed when removing cylindrical iron shavings from the hole. Easy to use Thanks to its design with clean edges, this hole saw cuts easily and effortlessly. The spring around the bit automatically pushes the washer out of the saw, immediately after completing the hole. Can be used with standard adapter in all drills with SDS-plus or hex chuck. Widely used: hole saw is often used in wood, plastic, aluminum, non-ferrous metals , copper, plasterboard and other materials. Suitable for bank drill, electromagnetic drill, pistol drill, impact drill, etc. Convenient for you.