DONN® SDX®/SDXL Acoustical suspension system has its own worth dictated in its economic and versatile approach. It has gained excellence over others on the industry for its simple installation, pocket friendly rates and ability to resist corrosion for quality performance. USG DONN® brand suspension systems and USG ceiling tiles can be used in a wide range of fire-rated floor/ceiling and roof/ceiling assemblies. - USG DONN SDX/SDXL24 Main Tee, Galvanized Steel, 12 ft.