Features: Use 2.4GHz ISM frequency band. Multiple selective channels supported for anti-interface from wireless. The circuit adopts special power amplifier tube, which has high working efficiency, clear and stable receiving image, and longer transmission distance. When using this system without obstacles, the wireless transmission distance can reach 500M Suppo rt 4 groups of channels. You can select these channels to avoid interference from signals. With extended frequency function, multiple frequencies can be extended to up to 8 using frequency. Suitable for AV output devices such as DVD, DVR and IPTV, etc. Supports video transmission of PAL/NTSC system and stereo audio transmission. There is no need to install software. Plug and play. Simple and convenient. Specifications: Frequency Band: 2.4GHz Working Frequency Range: 2414MHZ-2468MHZ(Standard) Extended Frequency: 2370MHZ-2510MHZ Using Channel: 4(Can be extended to 8 channels) 2-way Audio Signal Device: Audio (input/output) Channels, Video (input/output) Channels. Video Input/Output System: PAL/NTSC Power Of Transmitter /Receiver : 3W Input Voltage Of Transmitter: AC 100V ~ 240V 50/60Hz Output Voltage Of Transmitter: DC 12V 2A Input Voltage Of Receiver: AC 100V ~ 240V 50/60Hz Output Voltage Of Receiver: DC 12V 2A Plug Type Of Adapter: US Plug Transmission Distance: Approx. 3KM(in the open field), Approx. 5KM(with 24db antenna in the open field) Compatible: For AV output devices such as DVD, DVR and IPTV, etc Color: Black Size: Approx. 91 x 66 x 27mm/3.58 x 2.60 x 1.06inch Weight: 839G Note : The receiver and the transmitter must be connected to the antenna before power. Package List: 1 x Transmitter 1 x Receiver 2 x Power Adapter 2 x AV Connection Cable 1 x User Manual . Note : Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.