General description The Irwin Long Series Blue Groove 4X Flat Bits are engineered for efficiency, featuring a patented groove point and cutting edge that allows for cutting timber four times faster than standard flat bits. The design includes a parabolic scoop that enhances control and facilitates the removal of wood chips. Technical specifications Drill bit diameter: 20.0 mm Shank length: 400 mm Shank diameter: 10% larger than standard for added durability Increased relief angle: 17° (up from 12°) Other information 1 x IRWIN® Blue Groove 4X Long Flat Bit 20 x 400mm