16" x 36" or 36" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Black One model suits both T-Bar

One model suits both T-Bar and Drywall installations

Actual Filter Size – 35 3/4"w x 27 3/4" x 1"

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 8" or 8" x 10" duct opening (measured at the opening)

+ Product Details Size – 30"w X 8"h is the size for the duct opening measurement only

The process is intuitive: simply select the appropriate ceiling square for your grill

16" x 36" or 36" x 16" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Black One model suits both T-Bar+ Product Details Perfect Fit & Easy Sizing Designed for a 16" x 36" OR 36" X 16" duct opening (measured at the opening), with actual outer dimensions of 18. 5" W x 38. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 15. 75" x 35. 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