The Alfatron ALFMMX-4I-BT is a 4x HDMI HDBaseT input card designed for use with Alfatron MMX modular matrix switchers. Integrators and systems engineers building out installed AV environments can use this card to expand source capacity inside an existing frame, accommodating additional HDBaseT runs over CAT6 without introducing a new switching chassis. This is the correct choice when a project calls for incrementally scaling a matrix to handle more sources as a facility grows. HDBaseT over CAT6 is a standard approach in conference rooms, boardrooms, lecture halls, and multi-room installations where long-haul signal distribution is required without running dedicated coax or fiber. The ALFMMX-4I-BT accepts four such inputs simultaneously, allowing AV designers to route distant source signals into a centralized matrix from standard structured cabling infrastructure. Note that transmitters are not included and must be sourced separately to complete each HDBaseT run. For production environments or corporate installs that have already standardized on the MMX platform, adding input cards is a more cost-effective expansion path than upgrading the entire switcher. The modular architecture supports changes to the input configuration without disrupting other cards or the core routing engine already in service.