Enjoy music or TV sound without wiresanywhere inside the house or out Up to 250-foot range through walls, floors, windows and ceilings Great for outdoor settings rugged design, stable on uneven surfaces Easy and reliable tuning - phase-locked loop circuitry for a clear audio signal Omni-directional sound projects high-quality sound in all directions Automatic Level Control (ALC) avoids sudden volume blasts or valleys Dual power mode runs on optional batteries or the supplied AC adapter channel select switch allows you to optimize your reception Left-Mono-Right switch provides the option for stereo operation with the use of another AW822.