The Ruskin portfolio of life-safety solutions includes more than 70 models of 1½-hour rated fire and fire/smoke dampers that can be mounted horizontally in UL design I503, a two-hour fire-rated protective membrane made from steel studs and gypsum board. The FSD-LP series provides the most cost-effective energy-saving choice for building owners for its superb airflow performance, while DFD-LP provides excellent airflow performance along with installation- and maintenance-friendly features.
—Ruskin