Holbein Artists' Watercolor Pencils are water-soluble colored pencils. When you brush water over a pencil line, the color dissolves. The pencils are made for smooth drawing and for dissolving easily in water. The core is a thick 3.8mm, and the barrel is hexagonal.
The range has 50 colors. There is a 24-color set and a 50-color set in a cardboard box that has every color. Each color is also sold on its own.
The colors and color numbers match Holbein's artists' watercolor paints, so you can use the pencils with the same colors in paint. Go over a colored area with a wet brush to spread or soften the color.