SuperTooth DISCO Bluetooth A2DP Stereo Speaker for Apple iPhone 3G 3GS iPhone 4 SuperTooth DISCO Bluetooth A2DP Stereo Speaker (004085E) for Apple iPhone 3G 3GS iPhone 4 Internal subwoofer amplifier power 12 Watt RMS (real). Internal left / right audio power amplifier: 2 x 8 Watt RMS (real). Subwoofer speaker using Neodyne high efficiency. Left / Right full range speaker with parabolic membrane. Adjustable Volume Control. Optimal Sound Quality. MP3/MP4 connected by cable to line input stereo jack 3.5mm. Compatible with A2DP enabled devices such as Apple iPhone 3G 3GS iPhone 4 (Phone Not Included).