12" X 12" Aluminum Insulated Fire Resistant Access Panel Door For Wall / Ceiling Application (Lock and Key) With Frame - [Outer Dimensions: 13" Width X 13" Height] Fixed Blades with Damper + Product Details Size -

+ Product Details Size - 28"w X 16"h is the size for the duct opening measurement only

making it compatible with most thermostat models

ensuring consistent temperature control

Actual Filter Size – 31 3/4"w x 25 3/4" x 1"

12" X 12" Aluminum Insulated Fire Resistant Access Panel Door For Wall / Ceiling Application (Lock and Key) With Frame - [Outer Dimensions: 13" Width X 13" Height] Fixed Blades with Damper + Product Details Size -+ Product Details Size 12" X 12" is the size for the drywall opening measurement only, actual front end outer dimensions are 13" width X 13" height High Quality Strong and sturdy aluminum built to last. Design Aluminum material & color to give your space an attractive look & provide high durability corrosion protection no rust. Built in tumbler lock and key is provided Easy Access Provides easy access for HVAC, plumbing, electrical, crawlspace etc.