Press the button, super learning code can freely learn to match, can be unlimited matching receiver. The receiver is a distance of 300 meters (in an opening area), which may be affected by the environment and obstacles. Automatically save the selected ringtone after power off. Flexible design, convenient installation, no wires, save money and labor, and move freely. Built-in stereo speaker, especially suitable for office buildings, houses, factories, tourism and other places.