TriggerFoam Pro™ FireBlock is a professional grade, gun applied, polyurethane foam sealant designed to effectively block the spread of smoke and flame in Type V residential construction. It is more cost effective than fiberglass and caulks used for this purpose. NOT A FIRESTOP. Adheres to wood, metal, masonry and concrete. Seals gaps and joints, insulates, stops air infiltration and saves time and money. Ideal for use around pipes, wires and ductwork.