Industrial-type socket-outlets conforming to IEC 309 Standard, with mechanical interlock consisting of a circuit breaker enabling the plug to be connected and disconnected only in the open position, and the switch to close only with the plug inserted. Wide range including models with rotary switch and fuse holder base, characteristic miniature circuit breaker, and version with safety transformer. High application versatility thanks to the possibility of assembly in back-mounting and flush-mounting boxes.