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] Aluminum Bar + Product Details Size - Compatible with Duct 4" Product Details Size 32 LO246

+ Product Details Size - 32"w X 24"h X 2"d (for duct opening measurement only)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 10" x 26" or 26" x 10" duct opening (measured at the opening)

+ Product Details Size - 10"w X 20"h X 2"d (for duct opening measurement only)

+ Product Details Perfect Fit & Easy Sizing - Designed for a 16" x 28" OR 28" X 16" duct opening (measured at the opening)

the gap will expand and retract to meet perfect air supply needed

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] Aluminum Bar + Product Details Size Compatible with Duct 4" Product Details Size 32 LO246 + Product Details Size 32"w X 24"h X 2"d (for duct opening measurement only) + Product Details Perfect Fit & Easy Sizing Designed for a 10" x 26" or 26" x 10" duct opening (measured at the opening)