Under fire exposure, Window Wall Gasket rapidly expands (intumesces) to form a dense, highly insulative char to seal the void against the spread of flames and hot gases.Window Wall Gasket 8 Patent Pending•Designed for Window Wall and Hybrid Window Wall Construction•Compatible with common exterior grade sealants•Installs to top of floor or directly to panel framing•Tested to ASTM E2307 for Window Wall Assemblies Window Wall Gasket installs between the floor and aluminum framing directly behind the slab closure panel..