36" x 28" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Aluminum Bar scratch-resistant surface that gleams like

scratch-resistant surface that gleams like it's just been waxed

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 12" or 12" x 10" duct opening (measured at the opening)

+ Product Details Size – 18" x 30" or 30" x 18" is the size for the duct opening measurement only

Insulation density is 30kgs/cbm = 0

Actual Filter Size – 11 3/4"w x 15 3/4" x 1"

36" x 28" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Aluminum Bar scratch-resistant surface that gleams like+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 28" OR 28" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 30. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 27. 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