About this product [5-Mode Motion Sensor Alarm] Not only functions as a motion sensor detection alarm, it also offers other functions: Welcome/Doorbell/Alarm/Colored Light/Lighting modes. [36 Ringtones and 5 Welcome Doorbell Tone Languages] Welcome mode offers 5 welcome languages. Doorbell mode offers 36 ringtones. Welcome/Doorbell/Alarm modes have 4 adjustable volume levels. Colored Light/Lighting mode is silent with 4 adjustable brightness levels. [Sensitive and Wide Wireless Range] This motion sensor doorbell entrance alarm doorbell for commercial stores detects motion with a wide reception range, up to 280 meters/918 feet between the receiver and motion sensor. [Expandable Wireless Home] Flexible design tailored to your needs. You can choose the number of transmitters and receivers you need, freely combine them, and set specific lights or tones for each. Each receiver in this wireless doorbell features an alarm function and works with up to 32 motion sensors and eight remote controls. [Easy to Install and Use] The wireless doorbell can be used by connecting to a USB port or by installing batteries (the infrared sensor requires three AAA batteries, and the receiver requires three AA batteries). (Batteries not included)