The GR2721 uses reliable solid state sensing methods to monitor entires to high security locations. It has been tested to one of the highest security specifications, UL 634 Level 2. With solid state technology there are no moving parts, so the switch can reliably operate for millions of operations. The GR2721 includes pry and magnetic tampering protection. It is immune to shock and vibration that cause false alarms on other switch types. It is also resistant to lightning, static shock and radio frequencies. The GR2721 fits and industry standard ANSI recessed door cutout. It can be used on both wood and steel doors. Each switch set comes with switch, actuator, tamper plate and mounting hardware for easy installation. The GR2721 also has a unique output for misalignment. The GR2721 can be used to protect doors in high security locations; airports, biotechnology labs and other medical research settings, warehouses, manufacturing plants, jewelry stores, banks, data processing centers, military bases, ammunition depots, nuclear power plants, government facilities and energygeneration facilities.