Wireless FM Stereo RS 864 863.5 864.5MHz Rf cordless Stereo Headphones For TV VCD CD PC MP3 MP4 DVD built in 2.5mm to 3.5mm adapter w/Transmitter Online audio chat (built in Microphone at the transmitter) Wired headphone; Motile, portable, Use for MP3,TV, VCD, PC Operation distance up to 19M. Wireless reception from any electrical device with audio output such as full-channel TV sound, PC, game player System: FM with Radio; Carrier frequency: 85-108+-0.5MHz Power supply of transmitter: 2 x AAA or DC4.5V 100mA, Power supply of headphone: 2 x AAA