Synchronous electric clock movement, Ferranti Limited, Lancashire, United Kingdom, 1905-1987. Synchronous electric clock movement 1905-1987
Synchronous electric clock, sectioned, fitted with a 12-pole synchronous motor Synchronous electric clock 1931
Mains-driven synchronous electric clock in bakelite case, not self-starting, made in England by the General Electric Co. Ltd., trade marked 'SEC Electric', 200/250 volts 50 Hz, English patent 2634/31, estimated date 1931-1939 Mains-driven synchronous electric clock in bakelite case 1931-1939