The Donn SDX/SDXL Ceiling Suspension System offers maximum economy, simplicity, accessibility, and support for suspended ceiling installation. It's hot-dipped, galvanized steel construction provides corrosion-resistance and ensures paint adhesion. Working together with USG ceiling panels, they form the fastest-installing ceiling systems in the industry. Both the commercial remodeler and the DIY will find ceiling installation easy with the patented QUICK-RELEASE cross tee clip. The clips are easy-to-remove without tools, minimizing tee damage. An audible click when securing tee-to-tee connections ensures accuracy. The tight USG main tee splice yields sturdy, square ceilings. Length: 12 Ft. height: 1-16/25 In., flange width: 15/16 In. White. Fire resistant.