36" x 22" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w18h18 this 4-way air vent diffuser

this 4-way air vent diffuser allows you to precisely control airflow

+ Product Details Size - 32"w X 8"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 20 5/8" width X 14 5/8" height

+ Product Details Size – 18"w X 14"h is the size for the duct opening measurement only

listed size +2" diameter

36" x 22" Cube Core Eggcrate Return Air Filter Grille for 1" Filter w18h18 this 4-way air vent diffuser+ Product Details Perfect Fit & Easy Sizing Designed for a 36" x 22" OR 22" x 36" duct opening (measured at the opening), with actual outer dimensions of 38. 5" W x 24. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 35. 75" x 21. 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