Speaker specification: 40mm, 4ohms Input power: DC6-9V Output power: 2W+2W Frequency response: 200-18000Hz Have special electrical outlet of Ipod, suffle, nano and video etc. series products, can charge up IPOD series products while playing music. Can used with MP3、MP4、CD、Mobile、Notebook PC and so on. Directly insert U disk and MP3, can play music without audio line.