POLAR 31 ROUND - This individual white brush from Pro Arte is suited to watercolour painting. It has nylon filaments/hairs which tend to be more durable and harder wearing than other natural or man made fibres. Available in round, sizes from 0000 to size 20. Polar Flat brushes and Fan brushes are also available. POLAR 32 - These white polar brushes are very versatile as you can use them for all mediums as they use synthetic hairs. This particular range is suitable for flat washing and comes in various sizes from 1/8" up to 2" wide. POLAR 33 FAN - The Polar series 33 is a very practicle and durable synthetic brush. Suitable for all mediums, watercolour, acrylic and oils. This particular range are the fan brushes. Sizes small medium and large. Other Polar Series 33 are available in round and flat wash.