The Writers Edition Franz Kafka did not include a rollerball. If such a pen is offered it is a fake, and one that can be exposed from the edition's line-up alone, without examining a single detail. The pattern is a familiar one: counterfeiters transfer the decoration of a well-known edition onto shapes that never existed in the original, because a rollerball or ballpoint is far simpler to make than a fountain pen with a gold nib, a feed and a filling system.
Before buying a Writers Edition or any other limited series, then, it always pays to check against what was actually produced: which types of writing instrument existed at all, in what edition size, with what numbering and in what packaging. If even the type of instrument is wrong, any further examination of nib, engraving and finish is superfluous. Experience shows that buyers who point this out to disreputable sellers do not get the listing withdrawn, but at best convoluted wording added to the description afterwards, designed to shift the responsibility onto the bidder.