Ideal for outdoor painting Princetons Aspen combines several important benefits to artists the brush retains its shape for control and placement of color and the paint releases and glides evenly off the synthetic hairs. The brush can be used with all acrylic and oil paints including water soluble oils.Model NO PB6500SFB 4Brand Princeton Artist Brush CoPrinceton Brush Aspen Brush Short Filbert 4