The face paper of USG's Sheetrock Mold Tough Ultracode Core Panels is folded around the long edges to reinforce and protect the core, and the ends are cut square and even. The long edges of the panels are tapered, allowing joints to be reinforced and concealed with Sheetrock Brand joint treatment systems. The panels are UL Classified for fire resistance and can be used in any UL Design in which Type ULTRACODE panels are listed.