EASY INSTALLATION: As for this visitor chime, there are no wires to run, no installation hassles, the sensor is wall mountable. Place the correct batteries (3 AAA batteries)(not included), in the Sensor, make sure that the batteries have been put in the proper positions. Mount the Sensor properly by the front door, window frame, driveway, walk path, backyard or anywhere you need. Switch on the receiver and adjust the volume to the right position. Now the remote detective system is operating with the infrared detect technology. Place the Receiver in a place easy to reach. When the Sensor detects motion, the Receiver will make an audible sound u0026 the LED light will flash. Please wait for after switching on Sensor u0026 Receiver to activate. Receiver Switch Setting: 1)Music source: 38 different musics for optional, use the external button