Flintglas® MS Cap CoolStar® is designed for use as a cap sheet in built-up roofing systems. It is suitable for both new construction and reroofing applications over a variety of substrates. It is surfaced with highly reflective CoolStar granules to provide a durable, heat-reflective weathering surface when used as cap sheets. Non-modified, extra-strength fiberglass reinforced cap sheet with reflective CoolStar granule surface.