1. wireless doorbell to remind you of your guests by lovely songs. 2. 38 songs to choose from, and can be changed at the Press of a button. 3. easy to use, just place the sensor at the entrance for your entry and the receiver inside your home. 4. Great for home, office, hotel, store, etc. 5. alerts you when someone enters your entrance, walking, door or business, such as visitors, vehicles, intruders, animals or children who come or go. Receiver operating voltage: 110v-240v Transmitter operating voltage: 4.5v 3x aaa batteries (not included) Working range: up to 70 meters Infrared detection distance: 3-7 meters Button control receiver : Music source: 38 different songs Volume adjustment: high, medium, low Voice: can be configured with light and voice / with light and no voice How to use: 1. Place the correct batteries in the detector. 2. make sure the batteries are placed in the proper positions. 3. Mount the detector correctly through the front door, window frame, sidewalk, walk, yard or anywhere you need. 4. then turn on the receiver and adjust the volume to the high or low position. 5. The remote detective system is now operating with infrared detection technology. 6. Place the receiver in an easily accessible place. 7. When the detector detects movement, the receiver will make an audible sound & the LED light will flash. 8. Wait after calling Detective & Receiver to activate. 9. Install both units 3 feet above ground level for optimal performance. Plug Type:EU Plug,it applies to Indonesia, Germany, France, Spain, Italy and so on size:76 x 80mm Material:ABS colour:white Package Contents: 1 x PIR Sensor 2 x Receiver Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.