Vault vent covering

The  is a type of decorative item used in the Vault-Tec Vaults for air circulation and vent concealment. A covering covers a horizontal or vertical vent. The covering is a large metal circle with sloping sides wall-mounted to a wall by eight bolts. Five slats, angled downward, are placed within the covering. Coverings are located in corridors and rooms. Some coverings are placed in recessed sections of corridors for the free, unimpeded movement of residents. Coverings are periodically checked for maintenance and repair.

History of Vent Coverings in Vault 101
On August 3, 2274, Andy is repairing a vent near the Clinic.