Black Box Expansion ModuleBlack Box Expansion Module The Black Box Expansion Module is a pivotal component for the DKM HD Video and Peripheral Matrix Switching System, engineered to deliver unparalleled scalability and flexibility in professional AV environments. Designed as modular housing chassis with 2, 4, 6, or 21 slots and paired with transmitter and receiver interface cards, this expansion module enables seamless growth from small setups to large scale operations.