Description: Material: high-speed steel Hardness: 56HRC Clamping shank diameter: 19mm (Round) Model: 6.4/10mm diameter slotted (front square) Use matters: Square hole drill is mainly used for woodworking aspects. Various existing bits, can only process a circular hole, square hole can not be processed, to machining square hole, must drill the hole or cutting machine processed crude hole, then chisel made from artificial hand. The utility model in the hole drilled by the rotary body, while the impact of the use of hammer impact force transmitted to the outer body, the material crushing round hole and square head wall, a one-time processing of a square hole, and the dust can be broken slag discharged from the tube. Using different specifications of the square hole drill, matching the appropriate power of the square hole machine, you can play a square hole to meet the requirements. ★★Note:br> 1.If you have some problems about quality, please tell us and we will refund or resend to you. Please don't write bad reviews optionally, thank you.2.We will service for you at all times. If you have some problems about product, we will solve it as soon as possible and make you satisfied.