Description: 200 meters far away from the remote control (open area) to receive the doorbell antenna opened the best; Built-in 16 polyphonic ringtones suitable for different scenes, different styles, highlighting the taste; Built-in digital buttons, easy to adjust the size of the music sound; Three working modes are available: 1. music ; 2 blue flash; 3. + flash Can be effectively monitored from a variety of environments within the scope of its monitoring of human movement, detection range: 120 degrees, 5M of the human body movement. Infrared probe installed in the door, wireless doorbell on the house, when someone from the door to enter, the doorbell will be issued a reminder of the sound. Can be used for hotels, guest houses, guest houses, shops, offices, warehouses, offices, villas, homes. Specification: Material: Plastic Size: approx. 6.5 x 9 x 3cm/2.56 x 3.54 x 1.18inch, 6 x 9 x 4.5cm / 2.36 x 3.54 x 1.77inch Follow the steps for usage 1, Place the correct batteries in the detector & in the receiver units. 2, Make sure that the batteries have been put in the proper positions. 3,Switch Button to ON which is located inside the detector until after installing batteries. 4, Mount the detector properly by the front door, window frame , driveway, walk path , backyard or anywhere you need. 5, Then switch on the receiver and adjust the volume to either hi or lo position. 6, Now the remote detective system is operating with the infrared detect technology. 7, Place the receiver in an easy to reach place. 8, When the detector senses motion , the receiver will make an audible sound & the LED light will flash. 9, Please wait for 30 seconds after switching on detective & receiver to activate. 10, Please install both units 3 feet above ground level for optimal performance. Useful Tips Do not place the detector in areas where the wind will move it., also try to keep the detective in a clear path to the receiver, so that you can get optimal performance. Package Includes: 1Piece PIR Wireless Doorbell