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Sheetrock ® Brand AR Firecode ® X Panels (UL Type AR) are 5/8 in. (15.9 mm) Type X panels designed and tested to offer greater resistance to surface abrasion, indentation and impact damage than 5/8 in. (15.9 mm) Sheetrock ® Brand Firecode ® X Panels. These abuse-resistant panels feature a noncombustible gypsum core that is encased in 100% recycled, heavy duty face and back papers that form a high strength composite design. The 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 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 AR panels are listed. On the face, along the long edge of each panel, the UL Type Designation is printed for easy identification by building inspectors.