Tuff-Boy 1105 is a siloxane masonry water repellent that has excellent penetration, high alkali resistance, and low volatility. The siloxane resin actually chemically bonds to the masonry to which it is applied. Tuff-Boy 1105 is easy to apply and will protect masonry substrates against spalling, cracking, efflorescence, and other types of damage caused by the water entering the substrate. Tuff-Boy 1105 will greatly extend the life of the masonry to which it is applied by reducing the damage caused by repeated cycles of freezing and thawing. Tuff-Boy 1105 will also minimize leaching and migration of typical masonry discolorants such as calcium, sodium, and potassium salts. Tuff-Boy 1105 comes in a 30% high solids siloxane resin concentration.