Aluminum Oxide Grinding Wheel (1 Wheel), White, 120-Grit, 6" x 3/4" Single wheel 6" dia, 3/4" width, 120-grit Granulated aluminum oxide with a vitrified white bond Bushings reduce arbor hole to fit 3/4", 5/8", and 1/2" shafts Sharpens faster, with less danger of taking the temper out of the tool