It is used for monitoring and home audio and video transmission The wirelessly received image is clear and stable, the color is gorgeous, and the sound quality is clear and noise-free It supports PAL/NTSC video transmission and audio transmission With a full hardware design, there is no need to install software. The actual transmission distance depends on the customers' specific usage environment High power, long distance and enhanced signal transmission Specifications: Transmitter: Model NO. Usually it costs about 30USD-50USD. If you receive the item that not satisfied or defective, please do not open case and kindly notify us within 30 days.