Since the vibrant ink is specially formulated not to dissolve toner, you can work directly on photocopies. Broad and pointed polyester nibs are strong and flexible, allowing a variety of strokes from a single pen. The ink is alcohol-based, resulting in safer, better-smelling pens.COPIC Sketch markers are ideal for highly detailed work. It features a thin chisel nib at one end, and a durable pointed nib at the other, again replaceable. Since the same inks and colors are used in both COPIC Marker and COPIC Sketch Marker, they work together beautifully as a system.Use the pure solvent COPIC Blender with any copic Marker to soften previously applied color and produce color gradations, soft edges and highlights. Placed tip to tip, the Blender pulls ink from the Marker, then releases it in graduated dark to light tones as you draw.