Cold Air Return Covers. Cold Air Return Vent Cover by Shop Decorative Floor Vent Covers and Home Hardware The simplest ones are made of steel finished off with a scratch-resistant, no-scuff, shiny powder coat finish BA-IG-CA30 - 30" x 6" Invisagrille Flush Permanent Cold Air Return Cover
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VOISEN Return Air Grille,Fits 10x6 Duct Opening,Steel Return Vent Cover, White Vent Cover Grill for Sidewall and Ceiling,HAVC Cold Air Return Vent Cover,Overall Size:11.75" W X 7.75" H 4.9 out of 5 stars I can't reach them without a ladder but I'd say 1/4" out
Made of pine wood, our cold-air returns include a metal housing for 1" air filters while maintaining optimal airflow Fits 12x12 Duct Opening | Aluminum Eggcrate Return Air Grille | Low Noise & High Air Flow, Rust Proof Vent Cover Grill for Sidewall & Ceiling | White | Outer Dimensions: 13.75" X 13.75" Vent covers include a rubber gasket to seal vents, registers and associated duct work from contaminants, moisture, construction dust, mold, and fungi, and stop heat loss from cold drafts.
. A/C was changed out so this opening only acts as an air intake so no filters needed to be installed so only needed a grill to cover up the existing opening At first I wanted a super flat cover as well but then you have to worry it won't fit your inset
. Customize it by painting to match your walls or trim Others have a paintable white finish so that homeowners can easily match their cold air intake return grilles to their decor.