Fixed jam door that cannot be opened. It has vents, so air can be sucked in by the flywheels.
You need anti-jam mechanism, so I added the WithGuide version, for those who like to print in one piece.
There are three 2.5mm holes in the roof to connect things internally or externally.
It requires the original door axle. You may need to drill it better fit it in.

23rd Dec 25: I added a 25mm spacing version, so it will work work with Picatinny rail spacing.
It is 1 mm longer and with tighter friction fit, to hold the load from the rail attachments.
The rail has no trajectory correction angle, so you will hit above where you aim.

10th Jan 26: Added 6 deg Picatinny rail, and it works for me across the room (5m-8m) with a simple red dot.
Also the CAD files here on top of the STLs.