APOC Weather-Armor HT2 is an advanced roof underlayment and leak barrier for use under metal, tile, shingle and slate roofing systems. Weather-Armor HT² is manufactured using high melt bitumen, a high performance laminated polypropylene surface and highly flexible rubber polymers. These ingredients optimize performance in hot climates and under high heat conditions. HT2 is specifically designed to resist heat up to 265 °F. HT2 is a strong and durable underlayment and provides an ideal substrate when installing metal, tile, shingle, slate and other roof systems. This high performance waterproof membrane helps keep your home dry providing a cleaner and healthier indoor environment to live in.