I made these two plate-nuts on the manual mill today. 3mm thick Titanium (ASTM B265 - grade 2) sheet from Titanium Service. The plate-nuts measure 12 x 5 x 3 mm with 9 mm center-to-center for the M2.5 threads. The M2.5 screws are also Titanium - since we don't want to use magnetic materials for these parts.