content: Purchased this for my apartment just to protect sliding door and front door. First of all the unit had to be within about 10 feet of the front door to pick up the sensor. Deciding to work with this was a mistake. Within a few weeks the unit would start beeping for no reason and the only way to stop it was to completely turn off the unit. I am one of those individuals who normally bo not buy junk and i have learned another lesson.