20" X 20" Steel Flush Access Panel Door for Wall/Ceiling Application with Slotted Lock, Mud-in Flange - [Outer Dimensions: 21" Width X 21" Height] Color_Anodized Aluminum Can be hooked up with Compatible With Duct 7in Applications This sheet metal DDAG-A-1212

Can be hooked up with our "Butterfly Dampers" for precise airflow control

The total outer size of this grille is the listed size plus 2

actual front end outer dimensions are approximately 13

For example

+ Product Description Upgrade your HVAC system with our heavy-duty

20" X 20" Steel Flush Access Panel Door for Wall Ceiling Application with Slotted Lock, Mud in Flange [Outer Dimensions: 21" Width X 21" Height] Color_Anodized Aluminum Can be hooked up with Compatible With Duct 7in Applications This sheet metal DDAG A 1212 Can be hooked up with our "Butterfly Dampers" for precise airflow control The total outer size of this grille is the listed size plus 2