The Acudor A-FPS Series aluminum floor doors are designed for interior and exterior floodtight applications where water may rise above the surface opening.The angle frame construction with 4" high horizontal leg allow for bolting to the concrete. The diamond plate door panel is reinforced to 625 pounds/sq ft (capable of holding up to 10 feet head of water). The door panel overlaps the frame, compressing the gasket, providing for a floodtight fit.