Supper fidelity stereo effect, 100 meter RF frequency transmit RF (UHF CHANNEL) transmitter, CE Standard Multi-receiver allowed on same frequency 3 transmit channel, receive inching switch Connect transmit CD,VCD,DVD,MP3,TV,MP4,PC ect stereo audio source Apply MPX stereo modulate,MCU+PLL technology. MCU automatic check, auto-switch off when without signal Built-in rechargeable battery (optional) SPECIFICATIONS: RF frequency: RF frequency: 911-915MHz/863-865MHz/2.4GMHz Transmission power: <10mW Modulate method :FM Frequency response:20-20,000Hz SPL:100dB THD :<1% SEP>32dB S/N:>70dB Power supply headphone: Built-in 3V 2/pcs AAA battery, Power consume <26mA Power supply Transmitter: 12V DC adapter, Power consume <40mA Online service skype ID: robin926, ICQ ID: 300 732 551, MSN ID: cordialrobin contact person: Mr Robin Yang