1 Colorless Blender for Sketch Markers, the most popular of the Copic Markers. They are excellent for all forms of illustration, design, scrapbooks, fine art and more. They have an alcohol based ink that is permanent, non-toxic, low odor, and acid-free. Sketch markers have a 3-year shelf life and are guaranteed for color consistency. They can also be used with the Copic Airbrush System. With its outstanding performance and creative versatility, the Copic Marker System provides the ultimate solution to design flexibility and artistic liberty. These markers are fast drying, double-ended, and non-toxic, and come in a vast variety of colors. They are refillable, constructed in a unique design for a more comfortable grip, and so they will not roll away from you. Fit into a special airbrush system. Durable polyester nibs come in Medium Broad and Super Brush - a soft, flexible, fast-flowing brush for delicate or bold expression. Electronic production guarantees consistency of both color and output. Precise and positive colored capping system provides for instant color selection. Oval body profile is roll resistant on working surfaces.