Intumescent Wrap Strip Resilient Strip Designed to Firestop Combustible Penetrants Data Sheets: (SDS, PDS, etc…)Product Data SheetThe FlameSafe® Intumescent Wrap Strip (FSWS) is a highly flexible, resilient strip designed to firestop combustible penetrants in fire-rated walls and floors. Highly intumescent, the FSWS rapidly forms a dense char to prevent the spread of fire, smoke and toxic gasses when exposed to temperatures in excess of 250°F (121°C). The FSWS continues to expand up to 1000°F (538°C). Available in 12′ rolls, the FlameSafe® Wrap Strip is available in two widths and is easy to cut and fabricate. US Patent No. 6,207,085.