Having a long drive can be a bit of pain, especially if the entrance is a blind spot too, this means that anyone could drive up to your property and you would not even know it! However, this sensor takes the worry out all that and by placing the sensor at or near the entrance, you would be alerted of any vehicle or person entering the drive and so you can be prepared, the system can handle up to four sensors at one time.
These are the features and specs for the half a mile driveway alarm;
A remote motion sensor attaches to a mailbox post or address sign at the end of your drive and detects the movement of vehicles that pass up to 50′ away, sending a wireless signal back to the monitor in a home, ideal for homes with long driveways. The monitor generates a tone to alert you that someone is coming. The system supports up to four sensors (sold below) for homes with multiple entrances–a different tone is assigned to each sensor. An exit delay of five minutes allows you to set the monitor and depart without generating an alert. Sensor will also detect persons. Sensor requires one 9-volt battery that provides 9 months of operation; monitor plugs into AC with adapter. Sensor 4 1/2″ L x 3″ W x 2 1/4″ D. (4 oz.); Monitor 10″ L x 7 1/4″ W x 2 1/2″ D. (1 1/2 lbs.)
Priced at $179.95
Source [Hammacher and Schlemmer]
