USG Sheetrock Brand UltraLight Panels Firecode X are lightweight gypsum panels for firerated partitions that can be installed vertically or horizontally with aligned tapered edges on UL-approved 25-gauge studs.
Two UL type designations, ULIX and ULX, are available depending on geography. Both achieve the same strength and performance characteristics as USG’s standard 5/8-inch gypsum panels but at a reduced weight.