Expand-O-Flash® expansion joint covers are flexible, weather-proof exterior covers for expansion joint openings and are an effective, flexible closure for a wide variety of standard and special applications. Each Expand-O-Flash® cover is a combination of a flexible rubber membrane, supported by a closed cell foam to form flexible bellows, with two metal flanges, adhesively and mechanically combined to the bellows by a patented bifurcation process. As expansion joints move, the greatest stress occurs in the cover at the point where expansion joints intersect, cross or change directions. Factory-fabricated intersections are designed for maximum flexibility and are produced using special fabrication techniques to ensure watertight, clean seam lines. Close factory tolerance and quality control assures high yield performance.