Refill.Exchange.Mix. This empty Transformer body enables artistic freedom on several levels. It is not only refillable, but can also be combined with several exchange heads and tips. When using the different exchange heads, all tips (with different widths) can be put on top of the Transformer body. This way this Transformer can be pimped from 4 mm to 50 mm! The best: the marker is compatible with nearly all thin paints and inks. This way individual color shades can be mixed and then be stored in a clean way.