This set features three Color Brushes in black, gray and sepia. Color Brushes offer a portable alternative to traditional brushes. The nylon brush tip pen is flexible for an array of painterly effects and techniques. The ink flows easily, dries quickly and produces transparent watercolor effects. The set also includes a medium tip Aquash Water Brush that can be used to smooth and spread color. Water-based ink Refill cartridges are available Convenient design