The EMX Carsense 101 is a motion sensing system comprised of a sealed, wire-wound probe in PVC pipe; a lead wire of 50, 100 or 150 feet and a control module available in various voltages which plugs into the socket provided in the kit. If you can dig a trench, you can install this probe to activate anything that can be switched with a normally-open relay. . . turn on lights as you approach the house, open the gate as you approach, ring a bell to announce the approach of a vehicle. It's endless.