4 Port 3.5mm Audio Switch:4(1)-IN-1(4)-OUT 3.5mm Audio selector Designed for Customers Having Several Audio Sources and Outputs(Note: NOT a Splitter, Only One Input Can Be Played at a Time) Easy to Operate:4 to 1: Connect 4 Audio Sources (like CD Player/ Computer/ Phone) to 1/4 Ports and 1 Audio Output (like Speakers) to IN/OUT Port. 1 to 4: Connect 1 Audio Source to IN/OUT Port and 4 Audio Outputs to 1/4 Port With Audio Selector:You Can Select Audio Input Sources and Audio Output Devices by Selector(A/B/C/D). Volume Control on the Switcher Easy to Use Long Distance Transmission:Use Standard Audio Cable, Input and Output Transmission Distance up to 8 Meters. Plug and Play, No Need Power Supply(One 1m/3.4ft 3.5mm Cable is Provided) Wide Compatibility:Input Interface Is Compatible with PC, Phone, Laptop, Blue-ray Players and More. Output: Speaker, Headphones, Sound Bar and More Devices(Only for Three-segment Headphones, NOT for Four-segment Headphones)