36"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - White [Outer Dimensions 37.75"w x 37.75"h] Compatible with Duct 8" actual front end outer dimensions 14" Round Duct Pipe For 10 duct opening FR M 414 White

actual front end outer dimensions are approximately 12 5/8" width X 8 5/8" height

+ Product Details Size – 12" x 18" or 18" x 12" is the size for the duct opening measurement only

1/2” - 3119 PSI

75"H – fits a 18" X 8" duct opening

36"w X 36"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace Weather Resistant Air Grille with Screen Mesh White [Outer Dimensions 37.75"w x 37.75"h] Compatible with Duct 8" actual front end outer dimensions 14" Round Duct Pipe For 10 duct opening FR M 414 White actual front end outer dimensions are approximately 12 5 8" width X 8 5 8" height + Product Details Size – 12" x 18" or 18" x 12" is the size for the duct opening measurement only