【SIZE】3/4" (19mm) square chisel width, 75mm cutting depth, 210mm total length.【TIP AND EDGE】The best-designed drilling point tip and 4 cutting corners enable fast drilling with small opening resistance, and penetrating into working pieces of wood in precise opening size very smoothly and fast.【MATERIAL】Made of High-carbon steel, through heat processing, with high hardness (48-50 HRC) drill bits, and sharp-edged square chisel, durable and lasts long.【ADVANTAGE】With long drill core and square chisel, easy to lock the hole on the wood, can reduce labor intensity of construction workers, speed up the construction speed, reduce construction costs.【OPERATION】Used with mortise and tenon machine with double effect, and electric drill, hammer and other tools is required for punching square hole in wood.