This box gives you the ultimate control over your instruments and your gear. You can alternate between channels A and B or select both. Send one guitar to 2 amps or use it the other way around to select between 2 guitars into one amp. Thanks to our patented, state-of-the-art optical switching, there's no added noise, pops, or crackles. Indestructible foot switches let you make your choice with little effort and LEDs indicate channel status. Run it on one standard 9V alkaline battery.