Made to fit a 10" x 4" Duct Opening - Actual Dimensions are 11.75" x 5.75" Heavy duty steel air return vent cover Includes installation kits with screw for quick installation of air return register Size of wall vent cover shown made to perfectly fit duct opening Louvered design for look and better air flow Rocky Mountain Goods Air Return Grille is a heavy duty premium designed wall vent cover made to last the life of your house. With the complete installation kit, this air return register can be easily installed in seconds. For knowing the correct size we recommend measuring your duct and selecting the air return grille with the matching measurements. The attractive louvered design also ensures more consistent airflow throughout your house. The matte design is a premium finish but can also be used to paint if a different color is desired. Rocky Mountain Goods Air Return Grille comes with a lifetime warranty.