12" x 20" Pleated MERV 8 Filter for HVAC Return Filter Grille [Actual Dimensions: 11.75 X 19.75] 3-Pack sidewall + Product Details Perfect Fit Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 32" or 32" x 10" duct opening (measured at the opening)

actual front end outer dimensions are approximately 32 5/8" width X 10 5/8" height -

See our separate listing for Butterfly Dmaper to Control Airflow

listed size +1

+ Product Details Size - 36"w X 26"h is the size for the duct opening measurement only

12" x 20" Pleated MERV 8 Filter for HVAC Return Filter Grille [Actual Dimensions: 11.75 X 19.75] 3 Pack sidewall + Product Details Perfect Fit Compatible With Duct 7in Applications This sheet metal DDAG A 1212 + Product Details Perfect Fit & Easy Sizing Designed for a 10" x 32" or 32" x 10" duct opening (measured at the opening) actual front end outer dimensions are approximately 32 5 8" width X 10 5 8" height