rotary switch.Hot-swappable (no need to reboot computer). Super mini size:Easy to place and suitable for your desktop and office. Plug and play:No power supply and other software required; 't affect sound quality. Analog signal maximum support 2V p-p input and output. Input and output frequency range: 20Hz ~ 20KHz.Use standard audio cable, input transmission distance up to 8 meters, output transmission distance up to 8 meters. Main functions: Select audio input between (IN/OUT)A//D with 1/4 switch knob and get one output; Select audio output between (IN/OUT)A//D to receive one input; How to use: audio sources (like CD player / computer/Phone/MP3) to 1/4 ports and 1 audio output (like speakers) to IN/OUT port; connect 1 audio source to IN/OUT port and 4 audio outputs to 1/4 port. Colour:black Material:Aluminum alloy Package Contents: 1 x Audio Switcher Splitter 1 x Audio Cable Only the above package content, other products are not included. Note: Light reflection 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.