Square Hole Drill Bit, 4pcs Woodworking Mortiser Square Drill Bits, Spiral Drill Bits Kits Mortise Press, Wood Drill Set Space Hole Drill (6.4 Mm / 8

4 different size one set: 6.4 mm, 8 mm, 9.5 mm, 12.7 mm, meet your different needs.Made of high-speed steel, hardness 56HRC, lengthened core, sharp cutting edge, continuous blade, quick cutting, high efficiency, durale and practical, heat treatment, long life for use.Great for drilling square holes in wood with a mortising machine or a mortising attachment square hole drill is mainly used for woodworking aspects.High performance flute design geometry for superior chip extraction reduce labor intensity of construction workers, speed up the construction speed, reduce construction costs for construction, installation, renovation, decoration industries.