Excellent QualityThis square drill is made of high speed steel, sturdy and practical, high efficiency. Heat-treated cutting edge, high hardness, continuous blade, fast cuts. High-quality design The drill guide design of the bur provides effective protection against tearing at the beginning of use. No lag, the saw blade is automatically unloaded from the top of the hole on both sides, the drill bit is not blocked. Labor saving and precisionReduce the intensity of work of construction workers, speed up construction speed, reduce construction costs for construction, installation, renovation, decoration. Wide range of uses Ideal for drilling square holes in the wood with a mortiser or mortising attachment. Square hole drill bits are mainly used for woodworking. This drill cannot be used for electric drill or bench drill Wide ApplicationThis square hole drill bit is suitable for wood including MDF, plastic, particle board, canal wood, pine wood, basswood, etc. Note: It is not suitable for processing metal, glass, concrete, plasterboard, etc. Scientific matching and different sizes7 pieces per pack with different slot diameters to meet different your needs. Easily drill precise holes. Each drill is packaged in a single easy-to-maintain plastic case. This set of long square drill bits in different sizes can meet most of your needs. Easily drill precise holes. Mortise and tenon drilled square hole + outer sleeve in the middle of the combination Reduce the labor intensity of construction workers, speed up the construction speed, reduce construction costs for construction, installation, renovation and decoration industries: Use square hole drills of different specifications and match the appropriate power square tenon machine to make a square hole that meets the requirements. Alloy drill The drill bit is forged with alloy steel, the overall heat treatment hardness is high, and the service life is long Drill guide design :The cutting edge strength of the drill bit is on the same plane, which effectively protects it from bursting when first used. Chip flute: Standard chip flute design makes it easy to removal of wood chips from one side and improves efficiency Drill Bit Universal Shank Type: The drill shank adopts circular design, which makes clamping more stable. It is suitable for square hole machines and square tenon machines.