18"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 19.75"w x 23.75"h] Return Grille + Product Details Size - WD G128 Product Details Size 25 Floor Grille Toe Space

+ Product Details Size - 16"w X 20"h is the size for the duct opening measurement only

12" x 2" Decorative Wood Air Vent HVAC Duct Cover Grille - Polished Finish Red Oak Wood - 2-Way Air Direction

+ Product Details Size - 14"w X 20"h is the size for the duct opening measurement only

actual front end outer dimensions are approximately 18 5/8" width X 26 5/8" height -

Actual Filter Size – 31 3/4"w x 5 3/4" x 1"

18"w X 22"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh [Outer Dimensions 19.75"w x 23.75"h] Return Grille + Product Details Size WD G128 Product Details Size 25 Floor Grille Toe Space + Product Details Size 16"w X 20"h is the size for the duct opening measurement only 12" x 2" Decorative Wood Air Vent HVAC Duct Cover Grille Polished Finish Red Oak Wood 2 Way Air Direction