This high-security swing bar door guard is constructed of heavy-duty diecast zinc and comes in a satin nickel plated finish. The design of this door guard includes two high-security features; one is the T-shaped rotating thumbturn that will lock the bar in place when positioned vertically, and the other is the ball head arm that will allow only a few in. of secure viewing when answering to a visitor. This 3-7/8 in. hinged bar folds over a closed door to engage the keeper. This provides extra security for a safe viewing space, or for increased security with an open door for ventilation purposes. This door lock includes all necessary fasteners and plastic shim spacers for a quick and easy installation.