The DKM HD Video and Peripheral Matrix Switch System is comprised of modular housing chassis with 2, 4, 6, or 21 slots and transmitter and receiver interface cards. The DKM extender setup provides the widest range of possible combinations, which makes it easy to customize for your specific application. Four housings are available: desktop housing for two, four, or six boards or a 19-inch, 4U rack for 21 boards. A redundant power supply option is available in some housings. The 21-port chassis has an internal AC/DC power supply.