We are manufacturing This tool with a special diamond coating process which results in longer tool life than the electro-plated brazing method, diamond grit size is D427. Used in the boat and RV industry to trim laminated fiberglass boards. Cuts fast and clean, #44103, diameter (D): 3/8, cutting Height (B): 1, shank (D): 1/4, overall length (L): 2-5/8, replacement bearing: 47702, 44103 fiberglass carbon fiber and composite cutting diamond coated flush trim grit with ball bearing 3/8 dia x 1 x 1/4 inch Shank.