Easily monitor vehicle traffic and pedestrians with this driveway motion sensor alarm. This motion detector is perfect for locations that can't use a driveway signal hose. These locations include heavy truck traffic, forklift traffic, and areas that require frequent snow plowing. This kit does not use an air hose â?? instead, it detects movement up to 25' in front of it and rings the receiver chime each time the movement is detected from up to 1/2 a mile away. The sensor uses a 9-volt transistor battery and rings the two receiver chimes each time movement is detected from up to 1/2 a mile away. The sensor uses a 9-volt transistor battery. The chimes plug into an ordinary electrical outlet, produce a soft ring and have a built-in audio volume control. The driveway chime alarms will play one of twelve different tunes that are selected in the sensor. The flashing strobe ligh"Original" Bellâ?? are wired to each of the chimes using 5â?? of low-voltage electrical wiring included with this kit. The chimes have volume control and can be turned up loud enough to be heard through the door of many houses. The driveway motion detector chime kit includes all of the pieces necessary to set up your wireless driveway alarm