About this product [Entry-Level Motion Sensor Doorbell] Place the motion sensor at your front door, and the receiver will sound an audible alert when someone enters. This infrared motion sensor doorbell is ideal for offices, shops, and restaurants, and can play a welcome sound or music. [52 Unique Chimes and 5 Volume Levels] The motion sensor doorbell features 55 unique chimes, including alarms, doorbells, and welcome chimes in different languages. Five adjustable volume levels (0-110dB) and a silent mode cater to different occasions. If you set the receiver to silent mode, the receiver's LED will flash to alert you. [Wide Coverage] This wireless motion sensor features a 360° rotatable, adjustable bracket for a wide detection range. It can detect motion within a range of 2-7 meters and quickly sound an audible alert. A removable sensor angle adjustment cover allows you to adjust the sensing angle. In open areas, the operating range between the infrared sensor and receiver is approximately 230 meters. [Multifunctional Motion Sensor Alarm] The infrared motion sensor can be installed at a bedside or doorway to detect elderly or sick people. The motion sensor pager easily monitors when an elderly person gets up or leaves the room, freeing up caregivers to perform other tasks and remotely monitor activity. It can also be used as a store welcome doorbell or office doorbell. [Two Power Sources and Easy Installation] You can choose a long-lasting USB power supply or use three AAA batteries to power the sensor and three AA batteries to power the receiver. This ensures the alarm will function regardless of location or during power outages. Installation is simple with the included double-sided tape and screws. Please note that for optimal performance, the operating temperature range is -10°C to 35°C. Note: Batteries are not included. [Customer Satisfaction] Note: The USB cable and charger plug are not included.