Handheld Loop Resistance Tester with Range 0.0uΩ~10.000mΩ 1s～60s (10s step)

Gray Instrument Co. ZM-4B/U Resistance Bridge Industrial Instrument Engineering

Beckman Instruments Bridge ZM-30/U Resistance Bridge Military Communications

Taffet Electronics ZM-4B/U Earth Ground Resistance Meter Bridge

Vintage US Military Bridge ZM-30/U Impedance LCR Test Set (1950s/60s)

Signal Corps Resistance Bridge ZM4 B/U Serial No 98 Rare Vintage US Army AS IS

Conzerv EM6400 3 Phase Digital Panel Meter Energy Analyzer RS485 44-300V Control

Superior Instruments Co Model 670 Electrolytic Leakage-Ohms Vintage Untested