The fishtail stem (the F/T designation) was usually found on the longer and thinner models. This is the shortest and chunkiest F/T I've come across, and on a faceted-shank design no less. It's extremely difficult to make faceted stems as a categorical thing (such as the notorious 838 ODA), but to then add concave curves to the mix is borderline insane. I don't know why a pipe company would do that to itself.
Whatever the reason, the end result is distinctive, compact, convenient, and doubtless stable for a clencher.
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