36" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Adjustable Return + Product Details Size –

+ Product Details Size – 26" x 32" or 32" x 26" is the size for the duct opening measurement only

+ Product Description Protect your thermostat with the durable and tamper-proof Beige Metal Thermostat Guard

Actual Filter Size – 29 3/4"w x 15 3/4" x 1"

+ Product Details Perfect Fit & Easy Sizing - Designed for a 34" x 16" Or 16" x 34" duct opening (measured at the opening)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 18" x 16" OR 16" X 18" duct opening (measured at the opening)

36" x 30" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Adjustable Return + Product Details Size –+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 30" OR 30" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 32. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 29. 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