USG Sheetrock Brand Firecode X Panels are fire-resistant Type X gypsum panels that feature a noncombustible gypsum core. Long edges of the panels are tapered for easy finishing, allowing joints to be reinforced and concealed with Sheetrock Brand joint treatment systems. UL Classified for fire resistance, they can be used in any UL Design in which Type SCX panels are listed. The UL Type Designation is printed on the face along the long edge of each panel for easy identification by building inspectors.