MLCS Slot Cutter Router Bits are 3 wing cutters that create shiplap joints, tongue and groove joints, T-moldings, rabbeting. Three wing carbide tipped with 8 mm (approximately 5/16") bore, and 1-7/8" large diameter. Cuts 1/2" deep when used with our arbor and bearing. To reduce depth of cut, use larger bearings. Use for cutting slots or kerfs.