1. Backlight control - The backlight can be turned on or off by short the key 2. Reset energy - Long the key over 3 seconds until the energy data flash, then release the key, short the key again to reset the energy, otherwise after 3 seconds it stop flashing and the energy not be reset. 3. Data Storage When the power off, the energy data and backlight status can be saved. 1. Voltage Measurement range:AC50-300V Starting test voltage:50V Accuracy:1% 2. Current: Measurement range:0-100A Display format: Less than 10A display such as: 9.99A Less than 100A display such as: 99.9A Starting test current:0.02A Accuracy:1% 3. Active Power: Measurement range:0-30kW Display format: Less than 10W display such as:9.99W Less than 100W display such as:99.9W Less than 1000W display such as:999W Less than 10000W display such as:9.99kW equal 10000W display such as:30.0kW Starting test power:0.5W Accuracy: 1% 4.Energy Measurement range:0-1999kWh Display format: Less than 10kWh display such as:9.99kWh Less than 100kWh display such as:99.9kWh Less than 1000kWh display such as:999kWh Less than 10000kWh display such as:1999kWh Over the test range maintain the data, otherwise you reset it. Accuracy: 1% Note:The colors of some accessories are random, and the designation is not accepted, which not affect the use. Colour:White Material:Plastic Package Contents: 1 * AC Din Rail meter 1 * Power cable 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.