Panel fit and what that 1/4 DIN buys you
The PXF9APP2-MVVA1: The 96 x 96 mm face (1/4 DIN standard) drops into the same panel cutout as every other 1/4 DIN controller — no rework on the punch tooling. That matters when you're swapping a failed unit on a line-down call and the panel is already drilled.