Flame Stopper 5000 is an Advanced Flexible Intumescent Acrylic Latex Fire Stop Sealant designed to seal surfaces with or without movement. It "intumesces" or expands when exposed to extreme heat, cutting off the spread of fire through penetrations. Will not crack or deteriorate where vibrations occur. Stops the spread of toxic fumes, smoke and fire and dries to a red flexible seal. Apply in interior or exterior applications. Dried product can be painted.