The digital panel meter shows the reading of the input signal in digital form . These signal inputs such as voltage, current, or resistance are often measured from a sensor that is converted and displayed as temperature, pressure, and so on. https://youtu.be/zXKIeLaJyzk Specification: Range: DC 8.0-30V (No need for additional power) Reverse Connect Protection Display: Three 0.56'' LED digital tube Display color : red Refresh rate: about 500mS / times Input: DC voltage (<2 times the range) Resolution: 1% +1 digit Power Supply: DC3.0-30V (with the input common-line) Operating temperature: -10°c~ 65°c Package includes: 1 x DC Volt Meter Range 8 to 30V Led Digital Voltage Panel Meter Facebook Instagram Pinterest Video: https://youtu.be/MZveVY0gL_Q