Grace Digital GDI-AQBLT31 Indoor/Outdoor Water Resistant Add-On Accessory Wireless Speakers Accessory wireless speakers 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 on your yard or patio These are ACCESSORY wireless speakers. You must have a Grace wireless transmitter to play these accessory speakers Control the volume via your audio source or directly on each speaker Includes blue mood lights with on/off switch on each speaker to enhance your listening pleasure Connect the GDI-AQBLT31's to any of the Grace transmitters