3M's Fire Barrier Sealant (CP 25WB+) firestops blank openings and penetrations passing through fire-rated floor, floor/ceiling or wall assemblies and other fire-rated interior building construction. This halogen-free sealant is capable of expanding a minimum of 3 times its dried volume when exposed to temperatures above 1000° f. We engineered this sag-resistant sealant to exhibit strong adhesion to a full range of construction substrates and penetrants. Applied with conventional caulking equipment, this gun-grade sealant offers an excellent caulk rate, no mixing is required. In addition, this water-based sealant is paintable as well as re-enterable and repairable, offering easy application and clean-up.