BYK 347 is a silicone surfactant additive used in aqueous systems. BYK 347 produces a significant decrease in the surface tension and therefore particularly improves substrate wetting and leveling. It only marginally, if at all, stabilizes foam and the recoatability is not impaired. BYK 347 is characterized by its good substrate wetting properties, particularly also with thin-layered application. The additive does not increase the surface slip. BYK 347 provides excellent performance in applications requiring a reduction in surface tension and improved substrate wetting. It can be used in formulations that do not require increased surface slip.