The Size 2 Gainsborough Oil & Acrylic Filbert brush is made from Chungking hog's hair. This Professional-grade brush is generally the best choice for oil and acrylic paint due to the flags that hold color. The strong, durable brush easily manipulates heavy paint. It has a unique taper that causes the bristles to interlock, which maintains its original shape and helps control the placement of color. Filberts are a perfect compromise between rounds and flats. They are shaped like a flat with a curved end allowing for more flexibility than a flat. The side can be used like a round and the broad side like a flat. The Filbert brush was invented by the Impressionists in order to have the feeling of a worn in flat with maximum flexibility, and it has become a favorite of painters everywhere. Since 1905, Grumbacher has been a brand trusted by students, professors, art conservationists, and professional artists throughout the United States.