20" X 20" Aluminum Insulated Fire Resistant Access Panel Door For Wall / Ceiling Application (Lock and Key) With Frame - [Outer Dimensions: 21" Width X 21" Height] 10" Diameter Actual Filter Size – 19 4 X 12 Is CRFG2028 Width_14in

Actual Filter Size – 19 3/4"w x 27 3/4" x 1"

making opening and closing a breeze

ISO Supply Diffusers perform efficiently with air loadings of 6 to 30 air changes per hour (based on 10 ft

Premium Quality – Made of galvanized metal to prevent corrosion

actual front end outer dimensions are approximately 12 5/8" width X 8 5/8" height

20" X 20" Aluminum Insulated Fire Resistant Access Panel Door For Wall Ceiling Application (Lock and Key) With Frame [Outer Dimensions: 21" Width X 21" Height] 10" Diameter Actual Filter Size – 19 4 X 12 Is CRFG2028 Width_14in Actual Filter Size – 19 3 4"w x 27 3 4" x 1" making opening and closing a breeze