Features:   
1) Compatible size: iPod nano, iPod shuffle, iPod video
2) Convenient secondary input jack: for connection with other audio, devices, including
PC, laptops, older iPod, and other MP3 and MP4 players, and USB flash disks
(cable included)  
3) Impedance: 40 ohms   
4) Frequency response: 150Hz~18kHz   
5) Power output: 2W   
6) Power requirement: battery (AAA 1.5V 4), DC 5V (USB cable for PC), AC power adaptor
7) Cord (output: 6V, 300-800mA)   
8) Available color: silver, green