As a VU meter, with LINE and microphone inputs, can be matched well with most audio devices such as phone, computer, CD players, or speakers etc., very suitable for home/office/studio to dynamically decorate your auditory feast. As an audio adapter, easily to convert XLR (RCA) input to RCA (XLR) output and with IN/OUT switch, no need to plug in and out cables repeatedly to avoid wearing the contact point of the sockets.Multiple practical functions and easy adjustments: Gain adjustment, to adjust the gain of input signal, that is the swing range of pointer to get differnt display effects. Delay adjustment, to adjust the sensitivity of pointer that is the speed of pointer beating to adapt to different music styles.Environment noise filtering, can filter redundant noise and only retain the music from players, the pointer will swing more accurately. AGC and DB mode, the swing of pointer can be proportional (DB mode) or not proportional(AGC mode) to the input level, can be switched to get different display effects and fit different usage requirements.Powered by micro-USB 5V, power supply is only for providing power for the drive board of the VU meter, without any interference to the audio input and output circuit, the sound quality will not be affected.Unique and powerful design with exquisite appearance, cool black case and clear indicators looks vintage and dynamic. Mini size, convenient to carry and use, can perfectly match with a variety of usage scenarios.Audio input: stereo RCA / XLR / MicrophoneAudio output: XLR / stereo RCASensitivity adjustment: supportGain adjustment: supportDisplay mode: AGC / DBEnvironment noise filter function: supprtWorking voltage: Micro-USB DC 5V (above 1A)Voltage of backlight filament (tungsten lamp): DC 9-12VSettings saved after shutdown: supportDiameter of VU meter: 35mm / 0.11inDimensions(W x D x H): 152 x 115 x 50mm / 5.98 x 4.53 x 1.97inNet weight: 520g / 1.15lbColour: BlackMaterial: metalSize: 152 x 115 x 50mmPackage Contents:1 x RCA-XLR switch1 x USB cable (random color, don't accept the specified color)1 x screwdriver (random color and style, don't accept the specified color and style)Warm tips:1. VU1 PRO needs to be powered by separate USB power supply, don't use the USB port of computers or other equipments to power it, otherwise the VU meter pointer may move or noise may be caused because of audio input common ground.2. The audio input signal can only be connected to the audio output of ordinary players such as CDs, computers, mobile phones, MP3, etc.. Don't connect input of VU1 PRO to the output of amplifier or speaker, otherwise VU1 PRO will be damaged.Only the above package content, other products are not included.Note: Light shooting 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.