4 Port 3.5mm Stereo Audio Switcher: Bidirectional switching Splitter Audio Sharing active speakers and headphones Method 1: audios to (IN/OUT)A//D, use the 4 channel switch knob to get an output; Method 2: Connect an audio to IN/OUT, select an audio output between (IN/OUT)A//D; (The output can be switched between speakers and headphones) 4 channel switch knobs, fully isolated circuit, make sure that each signal is not affected by the other three channels. Plug and play; No External Power Required; 't affect the sound quality! colour:Black Material:Plastic size:7.8 x 4.8cm Package Contents: 1 x 3.5mm Audio Switch Switcher 1 x 3.5mm Audio cable Only the above package content, other products are not included. Note: Light 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.