Most RV's have a screen door on the inside of the outer door. A friend of mine installed a peep hole viewer in his outer door but the screen in the inner screen door obscures the view. What to do? Print a 3d screen door peep hole so you have a clean hole in the screen, but what about mosquitoes and other bugs? Make a door over it when you're using just the screen door. The whole thing is under 2 inches across.

I have printed this in PLA and PETG on my Bambu Lab X1c printer

To install, mark where the screen aligns with the peep hole and carefully cut a hole to match the inner part and push the outside part through the hole and through the hole of the inner part. A drop or two of superglue will secure it with the square top up. The door snaps into the ears on the inside part and lets you lift the door to reveal the hole and see out the peep hole. Lower the door to close the hole.