Hammond 1421SWM Series Screw and Cup Washers (M6) – Hammond 1421SWM50, A pack of 50 standard 16mm long rack screws with M6 threads and 50 steel cup washers with an outside diameter of 15mm.The screws feature a slotted oval head and have a nickel plated finish. Hammond 1421SWM50 Screw and Cup Washers Pk 50 pieces