QOR 24x5ml watercolor tubes in tin (7000020-0)QoR (pronounced core) watercolors feature an advanced archival, water soluble binder, Aquazol, that supports greater pigment loading than traditional watercolor binders. This allows QoR watercolors to provide more pigment strength and vivid depth of color in every brushstroke, while retaining the best qualities of traditional watercolors. The binder is used within the conservation community for painting restoration, and is more flexible and less