Incredible strength and conformability. That?s what you need for complete sealing around curved windows, window flanges, sill plates, corners, and joints. That?s exactly what you get in this quick-to-apply, peel-and-stick flashing. Thanks to a two-ply oriented, high-density polyethylene film mated to a premium butyl rubber adhesive and release sheet, it?s a highly durable solution for blocking air and moisture.