da Vinci Maestro Series 10 Kolinsky Sharp Round watercolor brushes are manufactured using male winter Siberian kolinsky red sable fur. These are top-of-the-line, highest quality brushes. They offer superior spring and control, plus unsurpassed water-carrying performance. All brushes have plated brass, seamless ferrules. The extra sharp needle-like point and longer tapered hair length of the Sharp Rounds result in faster action at the tip and the tightest snap at the point.