Princeton has done it again! More than 20 years ago, Princeton gave artists a synthetic version of sable that was almost the equal of fine Kolinsky and is still the standard of performance for its rivals. When we set out to create a synthetic version of squirrel, we developed a brush that may actually outperform the natural version. Neptune™ is our softest and thirstiest synthetic brush delivering oceans of color to the sheet. Experts in natural hair have been incredulous that this is actually synthetic. We are proud to offer Neptune™ in a beautiful range of shapes including mottlers and quills. The beautiful sea glass handles of our aquarelle brushes are the signature of the line.