Cover for the KCD4-20 Rocker Switch (16A/250V).
The bottom of the cover can be extended, or simply glued onto a surface.
The button itself snaps right in.
Model in the pictures used a 0.6 nozzle with 0.35 layer height (and old Prusament ASA signal white filament, causing print artifacts, but yolo).
The author remixed this model.
Extracted button geometry.