I lost the fins to this 8" b 8" exhaust fan cover years ago during a wind storm and regardless how much I searched have not be able to find replacements. So I designed my own.
Should fit standard 8" x 8" square covers.
Remove the 4 mounting screws that hold it into the homes frame and replace with ½" longer ones.
I recommend using washers to balance the load and not crush the part.
Print in PETG or ASA/ABS for longevity and outdoor UV protection
Can print without supports.
The author marked this model as their own original creation.