12" X 12" Steel Access Panel Removable Door For Wall / Ceiling Application (Lock and Key) With Frame - [Outer Dimensions: 13" Width X 13" Height] 18in diameter + Product Details Size -

+ Product Details Size - 26"w X 36"h is the size for the duct opening measurement only

Do not measure the overall size of the access panel itself

+ Product Details Size - 34"w X 34"h X 2"d (for duct opening measurement only)

Actual Filter Size – 29 3/4"w x 25 3/4" x 1"

12" X 12" Steel Access Panel Removable Door For Wall / Ceiling Application (Lock and Key) With Frame - [Outer Dimensions: 13" Width X 13" Height] 18in diameter + Product Details Size -+ Product Details Size 12"w X 12"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 13" width X 13" height Installation Easy installation just screw the sides of the access panel frame into your duct hole see photos for example. Our HVAC Access Door can be used in both commercial and residential settings. Design Easy access removable door provides easy access removable door for HVAC, plumbing,