SPECIFICATION: Input: special IPOD jack .3.5mm Mini stereo jack Power Output:3watts per channel IPOD player's charging and date transfer jack. Frequency Response:100Hz-20kHz Input Impedance:>10kohm Signal-to-Noise Ratio:80dB Battery Powered:3AA batteries or transformer Dimensions : Length 184mm 譝idth 135 mm 譎eigh 48 mm Weight: 340g DESCRIPTION: patibility-the stereo mini jack connection allows you to enjoy high quality audio from a variety of devices it's the best choice for ipod. 2.Digital amplifier technology provides you HI-FI sound effect. 3.Digital amplifier technology provides clear and more powerful sound while extending battery life. 4.Special ipod player jack .it can use 5v/12v transformer which compatible with ipod player.it is also can be recharging while transmitting date with computer.