A breakthrough brush for all media, Bristlon is a stiff white synthetic fiber designed for use in oils, water-mixable oils, caseins, and acrylic colors. Each brush has bristles with long-lasting interlocked construction and finely chiseled tips, providing excellent resiliency. After every stroke the brush returns perfectly to its original shape. BLICK Exclusive, Short Handle, Set of 5 - This Blick Exclusive set includes one each Round 00 (Series 1900), Round 6 (Series 1900), Bright 4 (Series 1902), Angle 3/8" (Series 1906), and Cats Tongue 4 (Series 1910). BLICK Exclusive, Long Handle, Set of 6 - This set includes brushes Round 0, Round 1, Flat 2, Bright 0, Filbert 1, and Script Liner 0. Brush sizes - The length and width of a brush of a given shape and size may vary by manufacturer as brush sizes are not standardized. Since fine art brushes are handmade, expect some variation even among brushes from within a single brush line.