You do not need to take into consideration the face size of the vent cover. Example: A traditional vent cover size can have a face size of 14×8, and neck of a little less than a 12×6. A standard linear slot diffuser is a modern looking decorative air vent cover that fits on a traditional air exit and replaces the traditional looking grills.

You do not need to take into consideration the face size of the vent cover. Example: A traditional vent cover size can have a face size of 14×8, and neck of a little less than a 12×6. A standard linear slot diffuser is a modern looking decorative air vent cover that fits on a traditional air exit and replaces the traditional looking grills.