KingBra Square Hole Drill Bit Woodworking Mortiser Drill Bit Steel Hardness Durable Mortising Chisel Set 3/4inch 19mm

Made of high-speed steel. Heat treatment, HRC48~50, high hardness, lengthened core, high concentricity. Great for drilling square holes in wood with a mortising machine or a mortising attachment. Fits all mortising machines and drill press attachments. Square hole drill is mainly used for woodworking aspects. It will get double effect by matched use with mortise and tenon machine.The square hole punching needs to use electric drill, hammer & other tools. Reduce labor intensity of construction workers, speed up the construction speed, reduce construction costs for construction, installation, renovation, decoration industries. Features: br Professional wood drill bit, suitable for construction, installation, renovation, decoration industry, etc. br Special steel, heat treatment, HRC48~50, high hardness, lengthened core, high concentricity. br It will get double effect by matched use with mortise and tenon machine, the square hole punching needs to use electric drill, hammer & other tools. br This quality set also comes with a convenient plastic storage case. br Specifications: br Material: HSS br Hardness: HRC 48~50 br Holder diameter: 19mm (circular) br Drilling core length: 200mm br Slotting flute diameter Total weight br 001 1/4″(6.4mm) approx 150g br 002 5/16″(8mm) approx 161g br 003 3/8″(9.5mm) approx 177g br 004 1/2″(12.7mm) approx 206g br 005 9/16″(14mm) approx 251g br 006 5/8″(16mm) approx 310g br br Shaft length: br 1/4″(6.35mm): 60mm br 5/16″(8mm):60mm br 3/8″(9.5mm):75mm br 1/2″(12.7mm):60mm br 9/16″(14mm):70mm br 5/8″(16mm):70mm br