0.8mm thick walls to help reduce the lines that appear with the stock mars pro lens array that recent machines seem to be having trouble with. You'll likely need to play with single/thin wall behavior, depending on your slicer. If you can't get it to slice, I've included a pair of files with a fixed grid thickness of 0.8mm that should slice without issue.

I've printed mine in PLA for testing and while that seems to be okay for the temperature from the LEDs I'd suggest printing it in ABS or ASA if possible.

26.5mm is stock height, 25.5mm gives you 1mm of room to shim to a different height if needed.