34" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter return filter actual front end outer dimensions Compatible with Duct 4" Product Details Size 32 LO246

actual front end outer dimensions are approximately 16 5/8" width X 14 5/8" height

actual front end outer dimensions are approximately 28 5/8" width X 26 5/8" height

+ Product Details Perfect Fit & Easy Sizing - Designed for a 36" x 28" OR 28" x 36" duct opening (measured at the opening)

+ Product Details Size – 12"w X 18"h is the size for the duct opening measurement only

+ Product Description The Clear Plastic Thermostat Guard provides reliable protection and security for your thermostat while ensuring optimal functionality

34" x 26" Cube Core Eggcrate Return Air Filter Grille for 1" Filter return filter actual front end outer dimensions Compatible with Duct 4" Product Details Size 32 LO246 actual front end outer dimensions are approximately 16 5 8" width X 14 5 8" height actual front end outer dimensions are approximately 28 5 8" width X 26 5 8" height