As a final layer of protection, this high-performance underlayment covers the entire roof after the WinterGuard application. It's reiniforced with fiber glass to provide extra resistance to wrinkling and tear out from fasteners. Roofer' Select meets the underlayment requirements for the CertainTeed Integrity Roof System which is comprised of underlayments, shingles, accessory products and ventilation all working together. The Integrity Roof System is designed to provide optimum performance--no matter how bad the weather conditions are. For more information regarding the Integrity Roof System click on the brochure link to the right.