Prodex Total 48 Inch Insulation, One 4 ft x 175 ft (700 sq. ft.) roll, R-16 Waterproof &amp; non-absorbent. Class A/Class 1 fire rated protection. Reflects 97% Radiant Heat. Provides 19 DB Soundproofing. Convenient flange tabs on sides. Does not mildew or promote fungus growth. Does not provide nesting for birds, rodents or insects. Is safe for workers to use as there are no fibers to breath or cause skin irritation. Easy to cut. More insulation value than 6 of common mass insulation. Can be stapled, nailed, glued or sewn.