DensDeck® StormX™ Prime Roof Board is a reinforced gypsum panel with enhanced moisture resistant core and coated glass mat facers. DensDeck StormX Roof Board is extremely durable and is approved for use in assemblies meeting FM Very Severe Hail (VSH) Classification, while still maintaining the highest level of moisture resistance through the use of GP's patented EONIC™ Technology. In fact, DensDeck StormX was the first gypsum cover board to meet FM VSH classification under a single ply membrane, and the first to do this under a TPO membrane (no fleece) as well. Choose DensDeck StormX Roof Boards for adhered and selfadhered "peel & stick" roofing systems, as well as hot mopped, cold mastic and torch-applied modified bitumen roofs. DensDeck StormX Roof Boards create a more resilient installation by enhancing the overall strength and wind resistance of an assembly, increasing the puncture resistance of the membrane, and providing hail protection to the membrane, insulation, and total roof system.