|"Did you receive the memo?"|
Air Vent 4 is the last and final air vent before your office, after Air Vent 3.
Air Vent 3 is an air vent with a X-patterned metal plating pattern. It leads from Air Vents 1 and 2. It also connects to Air Vent 4.
During gameplay, George and Maxie will crawl through this vent (one by one) to get to the Security Office. You can't stop them from going past this vent due to a lack of vent covers. Past this camera, Maxie and George will appear in the front window of the office, so there is no need to prematurely shut the door.