Here is a stereo audio AB switch for 1/8" (3.5mm) plugs that have three contacts on them. Send your audio to output #1, output #2, or neither if you put the switch in the middle position. (The switch on top has three positions and can be used as an audio on off switch.) This A B channel on/off selector can be used backwards too. Send in your 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. This item measures 2 x 1 3/8 by 5/8 inches thin (50mm x 35mm x 15mm) and weighs 0.53 Ounces (15 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. Remember, this switch is for plugs with three contacts or three sections on the end. If your audio plug has four sections on the end, or if you have a microphone headset then be sure to check out the other switch model I offer here on Amazon. Please let me know if you have any questions by contacting me here through Amazon. Have a nice day! -Clark