Trailer Roof Vent Trim Ring Only Black Plastic 2 Inch deep Fits Low Profile Vent

Black plastic material
Overall size 12.625″L x 6.625″w  
Inside dimension 10.50L” x 4.375″w
Trim ring max wall/ceiling thickness 2.00″
1.00″  flange width
6 mount holes x .188 diameter
Protects rough cutout edge from damaging to hand
Holes will need to be drilled into plastic flange to fasten to your wall/ceiling material..

https://dogboxparts.com/wp-content/uploads/2021/03/Plastic-Trim-Dim.pdf  Trim Ring cutout template