406 Secure Start® HT is a self-adhering, high temperature underlayment suitable for use as a waterproof underlayment in steep slope roofing applications with metal roofing, asphalt shingles, wood shakes/shingles, and mechanically-fastened roof tile. Secure Start® HT is recommended for complete roof deck coverage under metal and in areas with wind-driven rain, extreme temperatures, or climates causing ice dams. It serves a dual role as a flashing membrane, protecting areas susceptible to leaks such as valleys, roof-to-sidewall transitions, and around vents and skylights. Secure Start® HT is approved for use with Class A fire-rated, code-compliant shingle roof coverings.