Speed-Guardian 4000 U is a high-speed security door. The company says the door is ideal for exterior or interior door openings up to 22 feet wide-by-20 feet high and has an opening speed of up to 80 inches per second. The door has 1 5/8-inch-thick panel sections made of galvanized steel with a urethane foam core. Three vision options are available to accommodate many applications: double-pane windows, a complete vision panel and ventilation slats.
