Description1) 2.4GHz transmission and reception over three separate selectable2）with Wireless iPod Dock Transmitte3) Stereo channels4) Can be switched to receive either left, right or mono audio5) Individual adjustable volume control6) Indicator lights for power status and signal7) Speaker type per box: 4-inch bass driver and 1-inch high frequency driverSpecifications1) Maximum power: 15Wrms and 30Wpmpo per speaker2) Speakers auto mute, if no 2.4GHz signal is detected3) Battery: rechargeable sealed lead-acid 2,000mAh type4) Battery life: approximate six hours with normal operating levels5) Transmitter has three selectable 2.4GHz transmission channels, 1, 2 or 36) Sound input is from either headphone jack or line level (phone) connectors7) Transmission automatically ceases if no sound input signal is detected8) Remote control for speaker volume adjustment and muting function9) Transmission frequency: 2.4GHz10)Frequency response: 20 to 20kHz11)Signal-to-noise ratio: 75dB(minimun)12)Stereo separation: 75dB(minimun)13)Non-linear distortion factor: 1.5%(maximun)Accessories1) Main adaptors2) Headphone jack converter3) Remote control4) Audio cable5) Instruction manual6) Guarantee letter