For use under tile, slate, and metal roofing, Atlas Roofing’s WeatherMaster TU Ultra SE peel-and-stick SBS-reinforced 60-mil-thick underlayment comprises modified asphalt and woven polyester. It has a 260°F melting point, bonds with all-foam roof adhesives, and won’t slip under stacked tiles; a 3-inch selvage creates a waterproof bond between courses. Pricing varies for the 3-by-72-foot rolls (200 squares). atlasroofing.com