8" x 14" or 14" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 10.5" X 16.5"] w34h34 Actual Filter Size – 21

Actual Filter Size – 21 3/4"w x 17 3/4" x 1"

+ Product Details Size - 18"w X 18"h X 2"d (for duct opening measurement only)

This aluminum adjustable louvered garage vent allows air ventilation and circulation in your garage 24 hours a day

85" width X 15

Actual Filter Size – 23 3/4"w x 33 3/4" x 1"

8" x 14" or 14" x 8" Cube Core Eggcrate Return Air Filter Grille for 1" Filter - Aluminum - White [Outer Dimensions: 10.5" X 16.5"] w34h34 Actual Filter Size – 21+ Product Details Perfect Fit & Easy Sizing Designed for a 8" x 14" or 14" x 8" duct opening (measured at the opening), with actual outer dimensions of 10. 5" W x 16. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 7. 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