Properly labeled  switch cover including on/off, logical state, and electronic diagrams.

No more asking yourself "Is it up or down to turn the light on...???" Sure, you can observe the current state and just flip the switch the other way, but that won't work if the bulb is burned out. This switch cover eliminates the confusion.

Can be printed without AMS, using a color change at 6.0 mm. Supports are needed. OpenSCAD source code is included.