The Pro Arte Sterling Acrylix Brush Round Series 201 comes with Pro Arte's special Acrylix bristles, developed as a synthetic alternative to hog hair. The bristles are firm yet flexible, with a silky texture which they'll retain even after lots of use. They are extremely durable - you can leave them standing in water without damaging them - and the translucent white bristles make it easy to judge the colour of your paint. They are a delight to paint with, last for ages and are also less expensive than hog hair, so it's easy to see why they are so popular with artists working in acrylics and oils. The round version of the Pro Arte Sterling Acrylix Brush Series 201 comes in a range of sizes to suit all purposes.