<p>【High Quality Steel】This square hole drill bit is made of special steel, heat treatment, HRC48-50, offers high hardness, elongated core and high concentricity. Sharp blade, continuous, fast cutting, high efficiency.</p> <p>【How to Do the Work】: The square drill into the hole drilled by the rotating body, while the impact of the use of percussion force transmitted to the outer body, the grinding material round hole and square head wall, and the debris will be discharged from the tube at the same time.</p> <p>【Labor Saving and Accurate】: This professional mortising chisel ideal for drilling square holes in wood with a mortising machine or mortising attachment. And reduce the labor intensity of construction workers, accelerate construction speed, reduce construction costs for construction, installation.</p> <p>【6 Different Sizes】: 6 pieces in the package with different slot diameter to meet your needs. Comes with 6 different sizes: 1/4 inch 5/16 inch 3/8 inch 1/2 inch 9/16 inch 5/8 inch, suitable for opening different square holes.</p> <p>【Application】: Fits all mortising machines and drill attachments. Square hole drilling is mainly used for aspects of woodworking. Professional tip, suitable for construction, design, renovation, decoration, etc. Attention: the chisel alone does not work in a wood drill, you need an attachment for your drill.</p> <p>Delivered quantity: 6 pieces</p>