Summary

Basically, i found that a pc fan on a vent blocks cold are from blowing into the room so i made a little table to prop it up, the center is 13 cm in diameter, should be good for any pc case fan.

I found that a gyroid infill works best, around 5-10% depending on your fancy.
Please be aware that the middle is prone to breaking and bending (as seen in the video below)

Video about the print:
https://youtu.be/W_75_dNGGPA