Russian Black Sable, also known as Russian Fitch, is a portrait or realist painter's dream. This brush represents a perfect balance of the best qualities of bristle and sable. Black Sable is more stiff and substantial than Red Sable, but has an exceptional smoothness that leaves little stroke impression in the paint surface. The hair is extremely smooth. In fact, only certain master brushmakers at Da Vinci can form these fine tips without the hair slipping through their fingers. In the sun-filled rooms of the Da Vinci factory, production masters, interns, and apprentices sit at marble working tables. Visitors often marvel at the calm atmosphere not usually found in a factory. They often compare it to a laboratory or studio, as the silence of concentration prevails, interrupted only by occasional consultation and conversation. Brush hairs are glued into the ferrule by a dosing machine. Then the ferrule is filled with a modern component-glue. After the drying and curing process, all the hairs are firmly positioned. Da Vinci uses nickel- and gold-plated brass ferrules, which are rust resistant.