This specially formulated cleaning fluid is ideal for cleaning technical and calligraphic and inking nibs and pens. Use full-strength for clogged technical pen points and all other nibs with hard-dried ink. Dilute with water for periodic maintenance or for use in an ultra-sonic cleaner. Will not harm pen or airbrush parts. Rapido-Eze Pen Cleaner dissolves ink from technical pens airbrushes, and calligraphy pens. For best results, follow instructions on the container.