T-Screw Security Hangers provide a relatively quick and inexpensive way to deter theft and tampering when installing art in public places. These hangers are the most commonly used security hanging system, can be used on both wood and metal frames, and have built-in leveling adjustments. Additional T-screws can be used on large pieces or to convert cleat hangers to security hangers. Requires a special wrench to lock artwork into place. Available in single picture packs, economical bulk packages and as individual components.