The 3M™ Fire Barrier Sealant is an acrylic latex caulk used to firestop metal pipes and cables through concrete or gypsum and for use in dynamic head-of-wall systems. The 3M™ Fire Barrier Sealant is an economical alternative to firestopping applications. It is used to firestop metal pipes or cables through concrete or gypsum, and for use in dynamic head-of-wall systems. A single-part, sag-resistant, water-based acrylic latex sealant, 3M™ Fire Barrier Sealant 150+ has excellent adhesion characteristics to most common construction materials. In addition, since it dries to the touch within one hour, it can be painted for a more professional-looking job.