20" X 36" Steel Return Air Filter Grille for 1" Filter - Fixed Hinged - [Outer Dimensions: 22 5/8" X 38 5/8"] Aluminum Design – Fixed hinged for Suitable for all AC 8in diameter 12125SDCLNGBX

Design – Fixed hinged for easy filter change & cleaning - uses a 1" thick filter

+ Product Details Size - 25"w X 4"h is the size for the duct opening measurement only

+ Product Details Size - 18"w X 12"h is the size for the duct opening measurement only

Actual Filter Size – 15 3/4"w x 15 3/4" x 1"

20" X 36" Steel Return Air Filter Grille for 1" Filter Fixed Hinged [Outer Dimensions: 22 5 8" X 38 5 8"] Aluminum Design – Fixed hinged for Suitable for all AC 8in diameter 12125SDCLNGBX Design – Fixed hinged for easy filter change & cleaning uses a 1" thick filter + Product Details Size 25"w X 4"h is the size for the duct opening measurement only