Wireless Stereo Surround Sound hifi Rf Headphones for ipod, TV, VCD, PC , MP3 ,dvd, IPod with 3.5mm to 2.5mm adapter w/transmitter Fm Online audio chat (built in Microphone at the transmitter) FM radio Motile, portable, Use for TV, VCD, PC Operation distance up to 19M Carrier frequency: 85-108.5MHz