SIPERNAT® 38 is a specially engineered precipitated silica that has been developed for use in defoamers where its properties enable highly efficient destruction of both micro- and macro-foam. It can be readily surface treated using either a dry roaster in-situ process, and, as a micronized powder, its relatively small particle size and narrow particle size distribution make it the first choice for in-situ production of hydrophobic surface-treated silica.