Type S reversing magnetic contactors and starters are used for starting, stopping and reversing AC motors. Type S reversing contactors and starters are availble in NEMA Sizes 00 through 7. Type S contactors or starters can be mechanically interlocked so that only one device is energized at a time. The mechanical interlock is an interference (non-jamming) type, locking at the beginning of the stroke of any starter or contactor. The mechanical interlock is mounted on the underside of the reversing baseplate. This mechanical interlock is for two Type S contactors mounted horizontally. The mechanical interlock can be used with two NEMA Size 00, 0 or 1 two or three pole contactors. The 9999SM1 mechanical interlock is UL Listed and UL Component Recognized.