20" X 20" Aluminum Access Panel Gypsum Board/Sheet Rock Door For Wall / Ceiling Application (PUSH-LOCK DOOR) With Frame - [Outer Dimensions: 21" Width X 21" Height] Compatible With Duct 12in + Product Details Size –

+ Product Details Size – 8"w X 20"h is the size for the duct opening measurement only

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+ How To Measure An Access Panel Overall Size:

Actual Front End Outer Dimensions Are 12" Width X 8" Height - SEE IN DESCRIPTION HOW TO MEASURE A GRILLE

20" X 20" Aluminum Access Panel Gypsum Board/Sheet Rock Door For Wall / Ceiling Application (PUSH-LOCK DOOR) With Frame - [Outer Dimensions: 21" Width X 21" Height] Compatible With Duct 12in + Product Details Size –+ Product Details Size 20" X 20" is the size for the drywall opening measurement only, actual front end outer dimensions are 21" width X 21" height High Quality Strong and sturdy aluminum built to last and never rusts. Made with gypsum sheetrock for a seamless finish Design Aluminum frame material with sleek, shiny, durable white powder coat finish for an attractive look & moisture resistant to prevent mold & mildew buildup in indoor or outdoor