Firestop 400 Acrylic Sealant An intumescent acrylic sealant for internal pointing around door and window frames where damage due to smoke and flame needs to be kept to a minimum and in the small joints formed where fire rated partition sections meet. It has intumescent qualities which enable the material to swell under heat conditions to produce a fire and smoke resistant seal. Up to a 2 hour fire-rating can be achieved Good un-primed adhesion to most common construction materials Resists mildew and mould growth Remains flexible Easy to use, one component sealant Fire ratings achieved have been tested to BS476 Part 22//1987 (ISO834) and are specific to the conditions of test