Catalyst professional art brushes are yet another breakthrough that advances the science of synthetic hair. The fine craftsmen at Princeton created a new series of brushes that offer the stiffness and responsiveness you need, even in water. Catalyst brushes have real integrity in water, unlike natural hog bristles, which can be rendered useless when water-soaked. The true advance in these painting brushes is the Polytip bristles. For the first time, the tip of each individual hair has been split to replicate the natural flags found on the finest natural bristle. By giving each individual hair two to three distinct tips, Catalyst is able to hold a higher volume of paint while providing amazing detail and a smoother application. Designed for use with medium to heavy-bodied acrylic and oil paints, Catalyst paint brushes even push heavy gel media. Catalyst Polytip Bristle brushes truly are tools that move paint.