Features: Adopt LCD intuitive display screen for you to see the data more clearly, and with three modes for you to switch freely: POE mode, digital mode and analogs mode. POE testing function: This tool can be used for testing standard and non-standard POE device, it can also test POE voltage, power supplys polarity and power supplys mode. Voltagee test function: You can click "V" to enter the voltage test function, which can measure the battery voltage and voltage polarity and you can press "V" again to enter the POE test mode. You can measure the POE power supplys line and voltage. Adjustable sensitivity: when receiving signal is strong, turn down the sound gear;when receiving sianal is weak, raise the sound gear, which can give you a more accurate testing data. With LED flashlight function, you can turn on the flashlight in time when the light is weak or when you use it at night, so that you can use it normally in a dark environment.