Weve created the smallest guide bearings in the industry!, If youve Often wanted to trim and shape small details in tight corners, but were disappointed by the scoring and burning left behind by solid pilot bits, weve got what youve been looking for: eight of the most commonly used profiles In miniature sizes ? Complete with tiny miniature ball bearing guides. These bits are perfect for small fine work such as signs, lettering, small boxes, guitarmaking/luthier and toymaking; essentially any project that requires tiny flush trimming or shaping. Dont let the small size fool you; these bits are precisely machined and carbide-tipped., #MR0101, diameter (D): 5/16, cutting Height (B): 1/2, shank (D): 1/4, overall length (L): 2, flutes: 2, D1: 3/16, C: 1/16, MR0101 Miniature 5/16 dia rabbet with 3/16 dia ball bearing x 1/2 x 1/4 inch Shank Carbide Tipped router bit