BRB Siloen^® SR 619 is particularly well-suited for porous mineral building materials such as fired clay bricks (terracotta), sand lime brickworks, cement and concrete substrates (including cement fiberboards), aerated concrete, mineral-based (silicic composition) natural and artificial stone, as well as mineral plasters and paints. It provides rapid development of water repellency with minimal to no effect on the appearance of the treated surface.