1Measurement of electrical parameters: AC voltage/ current/ active power/ frequency/ power factor/ energy,6 in 1. 2Power zero-clearing mode: key zero-clearing, automatic zero-clearing. 3Display Type: LCD display, blue backlight;-Multi-screen display, 4Blue backlight brightness adjustable: highlight, low light, not bright. 5The voltage, current error and other options can be calibrated by the button itself.