34" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_R-4.2 Yellow Experience improved airflow dynamics and

Experience improved airflow dynamics and reduced noise thanks to its long neck body design

Actual Filter Size – 31 3/4"w x 27 3/4" x 1"

+ Product Details Size - 34"w X 36"h is the size for the duct opening measurement only

very easy to do

Actual Filter Size – 15 3/4"w x 19 3/4" x 1"

34" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter Color_R-4.2 Yellow Experience improved airflow dynamics and+ Product Details Perfect Fit & Easy Sizing Designed for a 34" x 26" Or 26" x 34" duct opening (measured at the opening), with actual outer dimensions of 36. 5" W x 28. 5" H. Please check the measuring guide to ensure a proper fit. Filter Size 33. 75" x 25. 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