Features: UT18B can provide AC and DC voltage (including the three-phase alternating current) measurement, phase of three-phase AC power indicator, on-off test, RCD Test, single pen measurement (can determine the zero line or wire), elf checking, no battery detection and other functions. Suitable for: smelting, electronics, manufacturing, defense, electric power, petroleum, chemical industry. More detailed product information, please refer to the English manual.. Auto Range RCD Test LED Indication Phase Rotation Test Single Lead (L2) Voltage Detection Self-inspection No Battery Detection Polarity Detection High Voltage Indication Low Battery Indication Auto standby Silent Mode Work Light