PITT Artist Pens from Faber-Castell feature pigmented India inks that are lightfast, acid-free and pH neutral. The ink is odorless, waterproof and permanent once dry on porous surfaces. The ink will also not bleed through paper making them ideal for sketchbooks. Pitt Artist Pens are used daily by artists worldwide for illustration, fashion design, life drawings, portraits, sequential art and canvas paintings.  Designed for deep detail, Ideal for bullet journaling, sketching, illustrating and hand lettering, They work beautifully on all types of papers and canvas, Highly pigmented ink, Reliable and consistent flow of ink, Store horizontally when not in use