Model 57 (electrical instrument & electrical measuring instrument)
Steel cased, black painted d.c. ammeter, to measure 0 - 15 amps d.c., made by the Weston Electrical Instrument Co, Newark, U.S.A.
Steel cased, black painted d.c. ammeter, to measure 0 - 15 amps d.c., made by the Weston Electrical Instrument Co, Newark, U.S.A.