20" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_R-4.2 Yellow + Product Details Size –

+ Product Details Size – 18"w X 25"h is the size for the duct opening measurement only

+ Product Details Perfect Fit & Easy Sizing - Designed for a 26" x 36" OR 36" x 26" duct opening (measured at the opening)

Our filter grille latch is easy to use on your fingers and requires no screwdriver to open

+ Product Details Size - 16"w X 10"h is the size for the duct opening measurement only

+ Product Description Protect and secure your thermostat with this high-quality Clear Plastic Thermostat Guard

20" x 14" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_R-4.2 Yellow + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 20" x 14" OR 14" x 20" duct opening (measured at the opening), with actual outer dimensions of 22. 5" W x 16. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 19. 75" x 13. 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