This instrument is to measure Conductance of Electrolyte solution or its Resistance directly. Working frequencies are 50 Hz and 1 KHz. Direct calibration in MHO. Resistance 0.1 Ohms to 1 Meg ohms. Conductance 1 MHO to 1 Micro MHz in seven ranges, Accuracy ±1% mid scale and ±3% on both ends. Null detection on meter with Conductivity Cell.