Irwin 4X Blue Groove Long Flat Wood Drill Bit

The Irwin Blue Groove 4X Long Flat Bit in 10mm x 400mm is one of the most versatile sizes in the range, ideal for general carpentry, joinery, and construction applications. This diameter is perfect for drilling holes for standard bolts, electrical conduit, plumbing pipes, and a wide variety of fixings through deep timber sections. The 10mm cutting diameter combined with the 400mm extended shank makes this bit indispensable for drilling through floor joists, wall studs, and roof timbers where standard length bits fall short. The patented groove point and cutting edge technology ensures the bit cuts cleanly through timber rather than scraping, delivering drilling speeds up to 4 times faster than traditional flat bits. The parabolic scoop design maintains excellent control whilst efficiently clearing wood chips from the bore. With an enhanced relief angle of 17° and a reinforced shank that's 10% larger in diameter, this bit combines speed with durability for professional-grade performance day after day.