Pébéo Iris Gold brush The range of Pébéo Iris Gold brushes, in synthetic bristles, is a high quality range. This brush in golden polyamide fibers combines qualities of strength and elasticity, and allows a line of great precision. Polyamide fiber brushes are very practical for creative hobbies and very versatile. Synthetic fiber is particularly used with water-based paints such as acrylic paint or watercolor. The Iris Gold brush can also be used with creamier and pasty paints. It is ideal with a number of techniques.