Johns Manville Sound & Fire Block® Mineral Wool Insulation Batt 15.25" x 47" (49.7 sq ft)

Johns Manville mineral wool batts are made of inorganic fibers derived from basalt, a volcanic rock, and are enhanced with glass fibers. The advanced manufacturing technology ensures consistent product quality with high-fiber density and low shot content for excellent performance. High-density material, with a melting point of 2,000 degrees Fahrenheit, inhibits the spread of smoke or flame and gives extra time for evacuation.