3M™ Fire Barrier Caulk CP 25 WB+ 27 Fluid Ounces Cartridge 3M Fire Barrier CP 25 WB A premium elastomeric latex caulk designed for use in a one-part fire, smoke, noxious gas and water sealant for through-penetrations. No-sag, non-halogen formula; fast-drying tack-free in approximately 10-15 minutes, paintable. Up to 4 hours Fire Protection. This product is great for through penetrations and may also be used for fire rated construction joints. A silicone sealant that is ready-to-use, gun-grade, one component silicone elastomer that cures upon exposure to atmospheric humidity to form a flexible seal. Provides up to a four-hour fire-rating. Compression/extension recovery or + or - 15% or original joint width. 3M Fire Barrier 1003 Silicone Sealant