The only parts recommended by Ford Motor Company for Ford, Lincoln, and Mercury vehicles.The Motorcraft Alarm Switch Assembly is a single-pole/single-throw, normally closed, grounding-type door-ajar switch that is mounted in the vehicle's door latch. When an open door causes an open or broken circuit to ground, the switch triggers the vehicle alarm system.The Motorcraft Alarm Switch Assembly is engineered and manufactured to exact Ford OE specifications to ensure OE quality and performance.