We don't think we can call this a pure-bred Parker Challenger. It seems to us that some long-ago repair person fitted it with a new cap band and section. We don't think that Parker Challengers ever came with an ink-view window. And although this section fits well in the barrel, the grip seems a size to small for the barrel. Regardless, we restored it with a new ink sac. ANNNND, it is a great writing pen with a delightfully smooth medium-point 14k gold nib! Our vintage pen shows the wear of past hard work, but there are no cracks. Ready for more hard work, this pen can make for a great daily driver. 13cm capped.