Protectosil CHEM-TRETE BSM 400 brings you the next generation in silane technology. Our chemists have developed a pure silane that yields a water repellent with the longest service life available, unsurpassed performance on brick masonry and the lowest possible levels of volatile organic compounds. Protectosil CHEM-TRETE BSM 400 can be applied in the most extreme temperature conditions without changing the surface appearance of the substrate. By penetrating the surface and creating a chemical bond, Protectosil CHEM-TRETE BSM 400 permanently attaches to the substrate. It is ideal for use on exterior above-grade brick masonry, concrete and most natural stones. By reducing the amount of water entering the substrate, Protectosil CHEM-TRETE BSM 400 reduces the intrusion of waterborne contaminants such as acid rain, salt and dirt, and reduces the deteriorating effects of these contaminants, including spalling, scaling, efflorescence, leaching and staining. Applicable Standards: LEED, NHCRP #244, ASTM E 514, ASTM G 53, ASTM D 1653, ASTM C 67