Electro-therm humidity and temperature tester, Model SRH77A, by Cooper Instrument Corporation. Includes original case, instruction panel, and attached cords. Box labeled SH44A, SH66A, SRH77A.

Electro-therm humidity and temperature tester, Model SRH77A, by Cooper Instrument Corporation. Includes original case, instruction panel, and attached cords. Box labeled SH44A, SH66A, SRH77A.