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 separate from the mounting pan on NEMA Sizes 3 and 4. Cams on the mechanical interlocks are operated by the contact carrier of each contactor. The mechanical interlock is attached to the underside of the two contactor baseplates on NEMA Sizes 3 and 4 This mechanical interlock is for two Type S contactors mounted horizontally. The mechanical interlock can be used with two NEMA Size 3 or 4 two or three pole contactors.