5 in 1wirelessHeadset product functions: 1. Wireless headphone functions 2. Headset with FM radio functions 3. wireless net chat 4. monitoring 5. wired earphone 6. super bass Transmitter *Transmitting frequency: 84 87MHz Power supply: AA DC 1.5v batteries 2pcs *Receiver Receiving frequency: 84 108MHz Max receiving range: 30m FM radio frequency: 88 108MHz