Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:4928895.

3.5in Drywall Cable Pass-thru for attic access to my closet rack.

I used a heat set insert on the fins with a socket head screw. The covers could be remixed to better fit the final amount of cables passing through. The included covers close completely. If you have many cables you might want to carve out a chunk.

Printing:

I printed it with 3 walls and 40% infill. No supports needed.

Updated to add a cover with provisions to weather seal around the cables. I used 1" foam weather strip and velcro strips.