The IRWIN® Blue Groove 4X Flat Bits have a patented groove point and cutting edge, designed to cut and not scrape the timber. Contains the following Increased relief angle from 12° to 17°. Sizes (Ø): 6, 8, 10, 12, 13, 14, 16, 18, 19, 20, 22, 24, 25, 28, 32, 35 and 38mm.
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