The monitor can be widely applied in AC 80-300V mains measurement, such as office, factory, laboratory, household and so on. You can use this item in RV as a way to view voltage to prevent issues with appliances.<br> You can use this item to monitor the voltage of other appliances; when this volt gauge displays too high or too low voltage, you can selectively turn off your appliances or equipment so as to prolong the life of your appliances.<br> Available Range: Widely applied in AC80-300V mains measurement.It enables you to plug in RV to monitor voltage for preventing issues with appliances<br> It's a must to let the children from the product. Do avoid using the product in a damp environment.<br> Potentiometer Adjusting : Just use screwdriver to open the outer coving, then adjust the potentiometer with small size screwdriver. Adjust potentiometer in counter-clockwise when it's excessive voltage, but if display voltage is too low, adjust potentiometer in clockwise.<br> Measuring accuracy: +/-1.5%, +/- 2 word<br> Measuring range: AC 80 - 300V (110V, 220V)<br> Consume power: less than 1W (about every 1200 hours consume 1 kilowatt-hour)<br> Number of digits: 3 digits<br> Potentiometer adjusting :<br> Please use the screwdriver to open the outer case of the voltmeter.<br> Then adjust the potentiometer with small size screwdriver.<br> If the displayed voltage is too high, please adjust potentiometer counter-clockwise.<br> If the displayed voltage is too low, please adjust potentiometer clockwise.<br> Plug Type:EU Plug,it applies to Indonesia, Germany, France, , Italy and so on<br> Material:ABS<br> colour:White<br> Package Contents:<br> 3 x Voltage test meters<br> Only the above package content, other products are not included.<br> Note: Light 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.