20" X 20" Steel Access Panel Removable Door For Wall / Ceiling Application (Lock and Key) With Frame - [Outer Dimensions: 21" Width X 21" Height] Grey Actual Filter Size – 29

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

[Outer Dimensions: 18

+ Product Details Perfect Fit & Easy Sizing - Designed for a 12" x 36" or 36" x 12" duct opening (measured at the opening)

actual front end outer dimensions are 25" Width X 19" Height

+ Product Details Perfect Fit & Easy Sizing - Designed for a 30" x 30" duct opening (measured at the opening)

20" X 20" Steel Access Panel Removable Door For Wall / Ceiling Application (Lock and Key) With Frame - [Outer Dimensions: 21" Width X 21" Height] Grey Actual Filter Size – 29+ Product Details Size 20"w X 20"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 21" width X 21" 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,