Specification: Material: High Speed Steel; Hardness: 50-55HRC; Square hole size: 9.5mm; Clamping shank diameter: 19mm; Drill bit shank diameter: 7mm; Square hole saw depth (max): 60mm; Total Length: 195mm; Fit for: Square hole machine. Note: If you do not have a square hole machine, you can use an electric drill with the included drill bit to start the hole, then use the square outer sleeve to form a 9.5mm square hole. Features: 1. Square hole drill is designed to be used with a square hole drilling machine (mortise machine) and is not intended for use on a standard electric drill alone. 2. The square hole is created using a combination of a center drill bit and an outer square sleeve. 3. Helps reduce labor intensity, increase work efficiency, and lower costs in construction, installation, renovation, and woodworking applications. 4. Intended for woodworking applications only. 5. The tool operates by rotating and transmitting impact force through the outer body to crush the material, forming a square hole in a single operation. Dust and debris are removed through the tube during operation. Using the appropriate square hole drill size and matching it with a compatible square hole machine allows for precise square hole cutting. Package Included: 1 x 9.5mm square hole saw drill bit