Square Hole Drill BitsThe square hole drill bits set can be drilled in wood and some composite materials, such as MDF, particle board, pine wood, basswood, etc. During use, please ensure that the board and the drill are at a 90 degree angle.These square hole drills of different specifications are commonly used in our daily life.Premium MaterialThe square hole mortise chisel drill set is made of the high quality steel. After heat treatment, the tool has high hardness, firmness and durability, and the square chisel is sharp and wear-resistant. The sturdy round handle helps you stay more stable during use.Groove DesignThe drill bits for square holes with high performance flute design geometry, combined with U-shaped edge, which can achieve excellent chip extraction and help you better improve drilling efficiency.AttentionsThe square hole drill bits are not suitable for a hand-held drill, it must be used with a mortise machine. If you want to use these square drill bits with a drill press, additional accessories will be required.