The Motion-activated Alert  is a convenient and affordable safety / security system. It features weatherproof  motion sensor which could be placed in the outdoor or indoor as  needed. Alerts with light and sound when vehicles or pedestrians approach within a 16 feet radius. Expandable up to 50 sensors, it is perfect for home, business, property and worksite.

Main Features：
Automatically ring the doorbell when a motion is detected
Weatherproof motion sensor for both indoor or outdoor use.
Low False Alarm Motion Sensor, Detects motion up to 16FT x 60°
52 ringtones(16 chord)to choose from and 4 steps volume control(up to 110dB)
Simple to use and easy-to-install without the hassle of running any wires
With up to 500FT operating range in open space,100m audible range
Eye-catching indicators alert you when the doorbell can't be heard
Expandable, allowing you to pair various transmitters to the receiver, the ringtone can be set to different for each push button
Using learning code to prevent interference from other wireless transmitters
Easy to choose your change and select your favorite ringtone with forward and backward button
Smart memory, automatically save selected ringtone after a power outage
High quality, approved with CE,FCC,RoHS certification