GENERAL PENCIL-The Masters Brush Cleaner & Preserver. This is a simple one-step total care process to keep your brushes performing like new! It works on oils, acrylics, watercolors, varnishes, glazes and most synthetic finishes. For use on sable, bristle and synthetic brushes. This package contains a 24oz tub of brush cleaner. Conforms to ASTM D 4236. Made in USA.