18" X 24" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER - EASY AIR FLOW - LINEAR BAR GRILLES Fixed Blades with Damper or diffusers

or diffusers

The integral multi-shutter damper with a convenient handle operator ensures that you can easily adjust the air volume

+ Product Details Size & Compatibilty - The 8" to 4" round metal pipe reducer & increaser 30 gauge is compatible with duct 8" to 4"

+ Product Details Size - 6"w X 36"h X 2"d (for duct opening measurement only)

18" X 24" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER - EASY AIR FLOW - LINEAR BAR GRILLES Fixed Blades with Damper or diffusers+ Product Details Size 18"w X 24"h is the size for the duct opening measurement only, [Outer Dimensions: 20. 5"w X 26. 5"h] Actual Filter Size 17 3 4"w x 23 3 4" x 1" High Quality High quality rust free, strong aluminum construction with smooth finished edges for easy and safe use; Filter grille features a user friendly plastic latch that requires no screwdriver for opening. Installation Location Sidewall and ceiling. Design Heavier gauge than needed,