Description Voltage display(voltage measurement) Current display (current measurement) Voltage calibration: Voltage +-9.5% adjustable Current calibration: Current +- 9.5% adjustable Intelligent transfer switch is designed to supply an single phase 220V load from different power supply, in order to maintain uninterrupted power supply of essential single phase load. According to voltage presence voltage quality on phases, it automatically select the optimum power supply and switch the single phase load supply to it. Specification:100A Color:As Shown Material:plastic Package Contents: 1 * Phase Selector(with printed words) Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.