Keyscan door control units are built for longevity, durability and reliability. Engineered by Keyscan, all 2, 4, and 8 door control units are designed for fast and efficient performance with standard features like dual on-board processors and heavy duty relays. Keyscan controllers are built for maximum flexibility and limitless expandability. And theyre all backed with Keyscans legendary customer service and technical support. Also known as -KeyScan - CA250 - 2 Reader/door Control Unit