1. 26-gauge galvanized steel curtain 2. Siliconized Polyester primer and top coat 3. Extruded aluminum bottom bar with structural steel angle for maximum strength 4. Dual lock assembly provides for two padlocks for added security 5. Heavy-duty galvanized steel guides hot dipped for maximum strength and rust resistance 6. Exterior polypropylene wear strip to reduce friction and ensure smooth and quiet operation 7. 9-1/2" drum assembly 8. Steel bearing shaft support 9. Adjustable tensioning device