MasterProtect® H 177 (formerly Enviroseal Double 7 For Brick) is a high-performance, water-based, clear silane / siloxane sealer designed for dense, vertical masonry surfaces such as hard-burnt brick. It repels water which extends the life of the brick, and provides brick and mortar with long-lasting protection against moisture intrusion. It is also transparent, non-staining, and breathable.