16"w X 10"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 11.75"h] 2-Way Actual Filter Size – 29

Actual Filter Size – 29 3/4"w x 19 3/4" x 1"

actual front end outer dimensions are approximately 26 5/8" width X 16 5/8" height

Actual Filter Size – 23 3/4"w x 13 3/4" x 1"

+ Product Details Size – 24" x 24" with 8" collar T-Bar drop ceiling perforated return grill - metal back casing

the second number represents the height

16"w X 10"h Aluminum Exterior Gable Louver Vent for Walls & Crawlspace - Weather-Resistant Air Grille with Screen Mesh - [Outer Dimensions 17.75"w x 11.75"h] 2-Way Actual Filter Size – 29+ Product Details Size 16"w X 10"h X 2"d (for duct opening measurement only); actual front end outer dimensions are 17. 75" Width X 11. 75" Height Weather and Pest Proof These louvers are especially designed to prevent water from entering your home, and with a built in back 1 2" mesh they also protect you from annoying rodents like mice, rats, birds, and squirrels High Quality Aluminum The premium durable aluminum will never rust and it will never