Opened for inspection. Please be aware that the outer box may have some dirt or tears, but the contents are in good condition, so please rest assured. [Bi-directional 4-Port Stereo Audio Switch] – The Cubilux 6.35mm audio switch allows for audio switching from 4 inputs to 1 output, or from 1 input to 4 outputs. It's plug-and-play, requiring no drivers or additional power. [Knob Control] – Easily switch audio channels with a simple twist. [Lossless Sound Quality] – The full aluminum alloy case and gold-plated 1/4 sockets completely shield against electronic interference, ensuring lossless transmission of audio signals without static or ground noise. [Wide Compatibility] - Compatible with stereo inputs or outputs, such as studio monitors, headphones, speakers, mixers, and amplifiers. Please note that this adapter does not support microphone input. [Perfect for Desktop Audio Systems] - The bottom has non-slip silicone pads, making it a selector that can be used on any surface.