TRANSMITTER, RECEIVER and 50 FOOT BURIAL PROBE. The Dakota Alert 2500 Wireless Vehicle Detection Kit with Probe is a driveway alarm kit that alerts you when a vehicle passes by or enters your driveway. When a vehicle drives up, the transmitter sends a signal to the receiver, which then alerts you by sounding the alarm. The receiver plays one of four different tunes. Different tunes are selected at each transmitter (additional transmitters sold separately) so that different zones can be distinguished. The receiver also offers a 5 minute exit delay so you can leave the house without disturbing any occupants. It also has a reminder beep and counter function. The detector probe is buried parallel to the driveway, and detects passing vehicles up to 12 feet away. The direct burial cable can be run to a tree or post nearby, where the transmitter box is located. This kit is ideal for monitoring locations where there may be deer or other large animals that would cause false signals with a typical motion detection system. The transmitter is weatherproof and ruggedly designed for long-term use in exterior locations. The receiver has four form "C" relay outputs and one 12VDC output. The output durations are adjustable up to 10 minutes. The transmitter operates on one 9-volt battery (not included) and has 50 feet of direct burial wire connecting the probe to the exterior case. The receiver is powered by a 12VDC transformer. Note: 2500 Series products will only work with other 2500 Series products and are not compatible with other Dakota Alert systems.