Mortise doors to fit hinges, locks, Lock Face plates and for general stock removal. All cutters fit threaded arbors, #55258, diameter (D) 1-1/4, cutting height (B) 5/8, thread 1/4"-28, flutes 2, 55258 carbide Tipped Mortising screw down Shear cutter 1-1/4 dia x 5/8 inch x 1/4 - 28 thread