Sealing small light gaps caused by trailer protrusions, the Frommelt Insulator dock seal helps prevent the entry of dust, bugs and other contaminants into a facility; its light-blocking header design features rows of layered, horizontal pleats that conform around protrusions as a trailer backs in. All trailer and forklift contact surfaces are made of reinforced Durathon fabric over a flexible vinyl base fabric. The seal’s corners are reinforced with layers of Durathon fabric and flexible, high-molecular-weight polyethylene sheeting. The head pad has a backerless construction that frees it from the wall and allows it to move with a trailer.