R-19 Kraft Faced 23" roll. 75.06 SF per roll. 6-1/4" thick. Roll is 39.16 ft long. Knauf insulation EcoRoll glass mineral wool insulation made with ECOSE technology contains a high concentration of one of the world's most abundant resources - sand and at least 60% post-consumer recycled bottle glass bonded with ECOSE technology. Knauf insulation ECOSE technology assures that no phenol, no formaldehyde, no acrylics or artificial colors are used to manufacture EcoRoll insulation. the consistent quality, low dust and easy cutting resilient fiber make EcoRoll the preferred choice.