A/B-Y Switcher with LED's for Switching of Source Signal Between 2 Amplifiers or 2 Sources to an Amplifier A/B-Y switching works two ways. It lets you switch a common source signal (guitar, bass or keyboard) between two amplifiers or amp channels. Or conversely, it lets you switch two source signals (ie, two different guitars) into the same amplifier. A good quality A/B-Y switcher will also provide LEDs or other indicators to show whether A, B or Y routing is in effect. The Y routing combines both the A and B outputs in parallel so that two amplifiers can be driven at once. The CoolSWITCH provides full A/B-Y switching functionality, plus parallel Common in/out jacks.Specifications: Power Requirements: 9V Battery (included) Dimensions: 3.75x2.5x1.5 inches (90mm x 63mm x 40mm) Weight: 1 lb (454g)