The Umbria filbert is a versatile and traditional brush shape, good for creating rounded flat strokes and for defining edges and getting into tight areas. Princeton 6250 series Umbria Brushes are perfect for oil and acrylic paints, but also work well with gouache and watercolor. The synthetic bristles are not as stiff as natural bristle, but have a more firm response than sable or white synthetic. An excellent choice for heavy body paints. The Velvetouch silicone sealed handle is comfortable to the touch and allows for smooth handling.