30" X 18" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER - EASY AIRFLOW - LINEAR BAR GRILLES Adjustable Return It can also be used

It can also be used with metal risers

Built-In Locking System – Comes with a permanently attached eight-tumbler lock and a supplied key for added security

Filter Grille features a user-friendly plastic latch that requires no screwdriver for opening

+ Product Details Size – 20" x 20" is the size for the duct opening measurement only

30" X 18" ALUMINUM RETURN FILTER GRILLE FOR 1" FILTER - EASY AIRFLOW - LINEAR BAR GRILLES Adjustable Return It can also be used+ Product Details Size 30"w X 18"h is the size for the duct opening measurement only, [Outer Dimensions: 32. 5"w X 20. 5"h] Actual Filter Size 29 3 4"w x 17 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,