In some manufacturing contexts, "MFC" stands for (used in furniture) or Mass Flow Controller (used in gas measurement). However, there is no standardized "Model 71" or "Samyrax" brand associated with these that is publicly cataloged.
The "Samyrax" guide to the MFC 71 system simplifies this complex rigging process into a manageable workflow. Here are the key features of the procedure typically outlined in such tutorials: samyrax mfc 71