The N-300 from Northern Computers is the basis for a completely autonomous access control system for one gate or door. Although technologically sophisticated, it is quick and simple to use, as well as compact and flexible in application. The N-300 uses proximity detection techniques to sense the presence of a unique tag allowing the automatic opening or unlocking of a door, gate or other access. The tag is a small, self-contained, automatic identification device, usually in the shape of a key tag or card. The N-300 consists of a compact, surface mounted access control unit containing an internal standalone reader. The system is programmed using programming cards or an optional hand-held programmer.