Electromechanical Telephone-Switching - Engineering and Technology History Wiki
DC-3GHz Sp8t RF Solder Pins/D-SUB 15pins Electro-Mechanical Relay Switch with N Type Connector Latching Type - China Transfer Switch, DC Relay | Made-in-China.com
Electromechanical switch - i12S series - SICK - IP67 / door / with separate actuator