This is ventilation air-intake adjustable grill, with uniform air difuser at ceiling level.
It is built for pipes with exterior dimension of (usually) 125mm and interior of 117mm. Screw is 5cm height.
Part 2 needs to be 3D-printed with some small support. Part 1 can be printed as it is. If print resolution is not very high it migh need some small polish on the screw at the end.
The author marked this model as their own original creation.