Princeton Artist Brush Neptune, Brushes for Watercolor Series 4750, Quill Synthetic Squirrel, Size 4 A beautiful range of shapes including mottlers and quills with rich wood tones and sea glass aquarelle handles Our softest and thirstiest synthetic brush, delivering oceans of color More durable and affordable than squirrel Soft and Supple with even release of color Our quill is a beautiful blend of silky smooth synthetic that performs like natural squirrel and holds a reservoir of water. Found in our Neptune line, the quill has a round ferrule and full belly with delicately pointed tip. Our Quill delivers beautifully sweeping strokes with incredible precision.