DAP® Blockade® is a single component, water-based intumescent, acrylic firestop sealant and is 4 hour system tested. It treats general firestopping applications for combustible and non-combustible penetrations. The intumescent expansion fills voids created by combustible materials burned during a fire. Blockade® also has exceptional sealant qualities, such as superb unprimed adhesion, excellent flexibility, easy gunning, and is paintable once fully cured. It is low in odor and cleans up easily with water. The red color is easily recognized as a firestop sealant. Interior use.