DuraFlex 190S SBS is a tough smooth surfaced, premium SBS (Styrene-Butadiene-Styrene) mop or cold adhesive applied membrane. Manufactured with a non-woven polyester mat and fiberglass strands for enhanced dimensional stability, high tear strength and puncture resistance. It is saturated and coated with high quality, asphaltic bitumen and SBS elastomers for a durable, flexible and easily maintainable membrane. Designed for use as a base sheet modified bitumen roof systems or as a cap sheet when surfaced with a flood coat of asphalt and gravel.