Grace Digital GDI-AQRCK41 Dual Powered Wireless Rock Speaker with Built-In Rechargeable Batteries (Discontinued by Manufacturer) Accessory rechargeable rock wireless speaker 150-Feet range Use batteries or AC power Add to any 2010 Grace Digital wireless system Works with GDIAQBLT300, GDIAQSHR200 & GDIAQSND100 900 MHz wireless technology for up to 150' foot range to listen to your stereo, iPod, or TV outside in your yard or on your patio This is an ACCESSORY rechargeable battery powered wireless rock speaker. It does not include the wireless transmitter. Play your speaker via the built in rechargeable battery for up to 7 hours. Plug it in the wall and the wireless rock speaker will play as it charges. Control the volume and power directly on the rock speaker or by adjusting the music source's volume level Connect the GDI-AQRCK41's to any of the Grace transmitters