Rare GPO No.57A ELECTRIC BELL with SPIRAL GONG c.1941 in Good Working Order

A G.P.O. No.57A large electric bell. Stamped on the back is "57A LF 41", the latter I believe to be the date of 1941. With mahogany case, brass fittings and spiral steel gong. It operates well on 9 to 12 volts d.c., with a nice "clanging" sound.

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