Audio Unlimited Outdoor Wireless Weather Resistant Rock Speaker System (2 Rock Speakers and Transmitter) The perfect system for today's consumer who is looking to add to, or expand, high quality music and home theatre sound taking it anywhere outside or inside the home. These beautiful synthetic granite portable speakers are powered by 900MHz Phase Loop Lock circuitry which automatically locks in and keeps the audio signal clear and strong within a range of up to 150 feet . The signal works just like high powered wireless 900MHz phones delivering a crystal clear signal through walls or any other obstacles in your yard truly offering endless installation options. The system transmitter supports all types audio inputs including RCA inputs for home theatre receivers, MP3 Players, computers and iPods.