Mounts to wall with provided screws. Overhang protects bottles from dust and debris. Twist off, tamper resistant tabs prefent leaking and are easily removed in an emergency. Holds factory-sealed, sterile, preserved, buffered saline solution bottles firmly in place for easy access in an emergency. Simple, highly visible, operating insutructions are provided on each unit. Durable, easy to clean plastic. Packing Type 16 oz double (2) Bottles