Specification:Item Type: 4 Way Analog VU MeterModel: VU4Material: Aluminum AlloyInput Voltage: 100-240VInput and Output Port: XLR (2 sets of XLR stereo)Large Audio Input Voltage: 2.5Vrms (Over this voltage it may damage the level meter)Maximum Effective Audio Input Voltage: 1.1Vrms (the maximum voltage that can be measured only full scale is displayed if it exceeds)Monitoring Frequency Range: 20-20Khz (VU mode) 100-10Khz (EQ mode)Input Impedance: 50KΩ high impedance has less effect on input audio and can be ignoredSupport Audio Source: Computer mobile phone decoder CD DVD player etc.Display Brightness Adjustment: Support 4 level adjustmentWorking Mode: VU standard mode EQ spectrum mode.Remote Control Function: SupportHand Swing Range Gain: 3 levels of gain adjustable -3dB 0dB +3dB (only adjust the hand swing range does not affect the source audio )Power Off Setting Data Saving: SupportSource: 1 set 2 set of LINE IN or built-in microphone pickupWorking Voltage: 12VDC 1ARemote Control Battery: 1.5V AAA x 2 (battery not included)Package List:1 x VU Meter1 x Charger1 x Remote Control1 x User ManualNote:1. Do not connect the speaker output of the power amplifier to the VU4. This will burn the level meter.2. If other power supply is used it must be 12VDC direct current with a current of at least 1A.3. In EQ mode if the needle swing is too large. It is recommended to lower the volume of the player appropriately.4. When the machine is out of the factory it has been debugged in VU mode by default. GAIN=0dB when the pointer of the meter points to the 0dB scale on the dial the input audio level is 0.775RMS 1KHz. If you want other voltage standards you can recalibrate yourself.