This is the core of the UFC filter changing system, the filter-chamber that contains the filters you are switching between when using the UFC system. UFC stands for Universal-Filter-Changer, and this is the core of that systems functionality. The universal nature of this system is possible due to the modular nature of it's configuration. This filter holder is compatible with the entire line of UFC adapters from Baader. This includes an extremely wide array of adapters to render the UFC Filter Changing system compatible with a large number of cameras and telescopes, as well as spacers for adjustment. This is the portion of the system in which the filter holder is inserted, and a required component for any Baader UFC system.