4 Pcs Woodworking Square Drill Bit Set 1/4?? 5/16?? 3/8?? 1/2?? HSS Wood Mortising Chisel Countersink Drill Bits Hole Saw Power Tool Kit

Specifications: Material: HSS (high speed steel) Hardness: Up to HRC48~50 Weights and Measures: 1/4 inch drill - bit diameter 6.4mm, shank diameter 4.4mm, weight 117g 5/16" Drill Bit - Bit Diameter 8mm, Shank Diameter 5.8mm, Weight 140g 3/8" Drill Bit - Bit Diameter 9.5mm, Shank Diameter 6.9mm, Weight 170g 1/2 inch drill - bit diameter 12.7mm, shank diameter 9.5mm, weight 210g

The package includes: 4 x square drill bits

Tip: - Drills with square holes cannot be used on an electric drill. Drill square holes must fit a square drill bit (socket and tap machine) for use. - If you want the square hole to be more beautiful, please chisel the detail part by hand.