The USG Sheetrock® Brand UltraLight Panels Mold Tough® are re-engineered, lightweight gypsum wallboard panels with a high strength-to-weight ratio composite design. The noncombustible, moisture-resistant core is encased in 100% recycled moisture- and mold-resistant green face and brown back papers. The green face paper is folded around the long edges to reinforce and protect the core, and the ends are cut square and even. The long edges of panels are tapered, allowing joints to be reinforced and concealed with USG Sheetrock® Brand joint treatment systems.