The StarWalker fountain pen can above all be unambiguously distinguished from the fake by the characteristic original nib; comparison photos can be found on relevant collector sites. The discussion about the transverse grooves primarily concerned the ballpoint, on which original and counterfeit are harder to separate. Important: an original StarWalker fountain pen can, by design, only be filled with cartridges, not with a converter, since the rough grip section contains a special component inside. If a converter fits, it is a fake.