Portable voltmeter with probes
Portable voltmeter with probes, probably for testing secondary cells, zero-centred scale 3-0-3, No. 121962 by Crompton Parkinson Limited, Regd No. 711338, English 1920-1940
Portable voltmeter with probes, probably for testing secondary cells, zero-centred scale 3-0-3, No. 121962 by Crompton Parkinson Limited, Regd No. 711338, English 1920-1940