Be warned when a door or gate has been opened. A backyard swimming pool area should be a source of pleasure and great memories and a safe environment for all to enjoy. There is no substitute for proper vigilance around swimming pools, backyard fountains and garden ponds. A safe swimming pool, whether above or in-ground requires proper fences of correct height with self closing doors secured with automatic latching mechanisms. In some locals a secondary fence within 4 feet of the pool is required. Check with your municipality. While no alarm can replace proper security, the SK637 can help warn of unauthorized access to the pool or other dangerous areas. The SK637 is a magnetic contact alarm that can be used both indoors and outdoors. One side of the contact is installed on the frame of the door or gate and the other contact is mounted on the door.