These popular insert router bit profiles provide all woodworkers access to the industrial-grade technology, at an affordable price. By replacing worn knives instead of sharpening standard carbide Tipped bits, router bit dimensions, cutting quality and accuracy remain constant during the life of the tool.#Rc-45910, diameter (D): 1/2, radius (r): 1/4, cutting Height (B): 1/2, shank (D): 1/4, overall length (L): 2-1/8, Type: core box, replacement insert knives: rck-266 (13x9x1. 5mm), replacement bearing: 47701, # of knives: 1, RC-45910 carbide Tipped insert core box 1/4 radius x 1/2 dia x 1/2 x 1/4 inch Shank 1-flute