Main unit: 115*35*70mm induction head: 80*60*40mm. 5 modes are available. It not only serves as a motion detector, but also has other functions: welcome, alarm, doorbell, color light, night light mode, 5-in-1 automatic doorbell The adjustable melody and volume receiver is a doorbell design with 36 ringtones and 5 doorbell sound reception to meet personal preferences.. Sensitive and wide range wireless motion sensors capture motion in large spaces, with a working range of up to 280m/918 feet between the receiver and the motion sensor. The detection range of the infrared sensor is approximately 4-8m/13-26 feet, allowing you to stay informed and safe at all times. You can place the motion detector on the porch, gallery, and place the receiver at home. The application of motion detectors is crucial in home safety systems. It can detect movement in the surrounding area - front doors, galleries, gates, walkways, apartments, offices, hotels, shops, and many other indoor spaces. And trigger an alarm to the connected receiver. It provides additional security for your property and loved ones. Easy to install and use, this device can be charged or battery installed through a micro USB. The infrared sensor requires three AAA batteries, while the receiver requires three AA batteries to function. Both infrared sensors and receivers have mounting bases. The infrared sensor can rotate 360 degrees from left to right and 180 degrees from top to bottom. Therefore, it is easy to install and can be rotated to any position you need. (excluding batteries)