This set of 3 hog bristle brushes is suitable for oil, acrylic and gouache painting. The set contains the following types and sizes: 3 round brushes in sizes 2, 6 and 10.Pig bristle (also known as hair) is a sturdy type of hair used for thicker paints, such as oil and acrylic colours. The bristles are flexible and create a pronounced brush stroke in the paint.