This is a two channel stereo audio AB switch. It will let you pass your audio through to output #1, output #2, or neither if you put the switch in the middle position. (The switch has three positions and can be used as an audio on off switch.) This A B channel on/off audio selector can also be used backwards. You can input two audio signals and switch to the one you want to come out the middle jack. You can let input #1 come out, input #2 come out, or nothing comes out. Also great for both TRS and TRRS audio plugs on headphones and headsets with a microphone. This item measures 2 x 1 3/8 by 7/8 inches thin (50mm x 35mm x 24mm) and weighs 0.84 Ounces (24 grams). No batteries required. The audio cables are not included so be sure to get the right lengths you need. This switch is hand built in Canada using quality parts. This item is packaged very simply, in a heavy gauge zip-lock type bag to reduce environmental waste and extra cost. Please let me know if you have any questions by contacting me here through Amazon. Have a nice day! -Clark