Chameleon Art Products, Chameleon Pen, Grass Green GR3 MIX IT UP - A special mixing chamber holds toning medium that infuses onto the marker tip, add a little for tones or add a lot for color tints MORE FOR LESS - Using our special mixing chamber, each pen goes from as light as a hint of a tint to rich tones, eliminating tonal gaps in your collection so you can do more with less ONE PEN TWO NIBS - Our pens feature a double-ended design- a Japanese SuperSoft brush nib and bullet nib, ideal for paper crafts, manga, graphic & fine art PROFESSIONAL QUALITY - Our alcohol-based is permanent on most surfaces, non-toxic, and low-odor LONG LASTING - Keep your pens top notch with our replaceable nibs and refillable inks