carbide teeth enable optimum performance, speed, and a 10x longer service life compared to standard bi-metal keyhole saws. The teeth can be resharpened. extra-large 25 mm cutting depth for drilling in sheet metal and pipes. one-piece construction with high concentricity and reduced vibration for precise drilling. depth limiter prevents overdrilling for maximum safety. ejection spring for easy removal of the drill core, prevents jamming and saves time. replaceable centering drill and ejector spring. The use of coolant extends the service operating life of keyhole saws. cutting oil is suitable for metals, turpentine for aluminum, water for plastic, and dry drilling for cast iron. suitable for drilling in steel (< 1200 N/mm²) up to 4 mm, stainless steel up to 2 mm, aluminum, zinc, cast iron, copper, fiberglass, and plastic
