This is basic lens cap for the Optoma GT1080HDR (Regulatory No: DAEHHGNST) DLP Projector. The projector doesn't come with one and could really use one because the short-throw lens sticks out past the front of the projector. It has a concave shape for your fingers to pull it off. There's also a couple little nubs on the inside which are designed to grab the grooves on the outside of the lens / focus assembly. Print it with the flat side down, no supports required if your printer can handle a 50 degree overhang (most can).
I printed this on a Prusa Mini with Polymaker Tough PLA, Prusa Slicer defaults for Generic PLA (15% infill) with a 0.2mm layer height (QUALITY preset) and it worked fine.
The Fusion 360 model is also included.
The author hasn't provided the model origin yet.