34" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 3-Way or 4-Way Universal Fit – Measures 6"

Universal Fit – Measures 6" wide x 3-1-13/16" high x 3-1/8" deep

+ Product Details Size – 18"w X 28"h is the size for the duct opening measurement only

Installation of the vents will eliminate the need to raise the door ensuring security and constant air flow and reduced heat transfer into attics and adjacent house walls

the gap will expand and retract to meet perfect air supply needed

34" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter 3-Way or 4-Way Universal Fit – Measures 6"+ Product Details Perfect Fit & Easy Sizing Designed for a 34" x 16" Or 16" x 34" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 18. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 33. 75" x 15. 75" x 1" Premium Airflow Efficiency High performance cube core eggcrate design allows 95% airflow efficiency, reducing energy costs and maximizing HVAC system lifespan. Durable, Rust Free Aluminum