Description: ​ ​This is great for drilling square holes in wood with a mortising machine Specification ​ The square hole drill cannot be directly installed on the electric drill, drill square holes need to fit a square hole drill drilling (mortise and tenon machine) to use. Mortise and tenon square hole drilled by the terrible + outer sleeve in the middle of the combination. ​ ​Reduce labor intensity of construction workers, speed up the construction speed, reduce construction costs for construction, installation, renovation, decoration industries. ​ ​Arc design, exquisite sharpen durable. ​ ​Use matters: Square hole drill is mainly used for woodworking aspects. ​ ​ ​ ​Features: ​ ​ ​Name: Square Hole Saw ​ ​Material: Spring steel ​ ​Color: as picture shows ​ ​Product size: