I already did that comparison on the P&C thread, Don. The P&C N- series DBEs I checked are slightly longer than their Plomb WF- series DBE counterparts. Note that the P&C WF- series wrenches are also slightly longer than the Plomb WF- series wrenches. None of this is surprising. Plomb and P&C did not use the same tooling. The round-shanked P&C WF- and N-series wrenches are based on the P&C 22xx series wrenches that P&C was making before Plomb bought them out, and before Plomb used them to make WF- and N- series wrenches for Plomb contracts with the US Army Air Corps and possibly the US Navy, and before P&C made WF- series wrenches under its own contract with the US Army Air Corps.
Maybe I am missing your point. You're not suggesting a slightly different length makes them different wrenches, are you? I think the identical model numbers, the identical opening sizes on the box ends, and the pattern (15* angled heads) make them the same wrench, regardless of the shape difference (round vs flat shank) and the negligible length difference. If they were dwarfies, or offsets, or something serious, that would be problematic. Whoever the customer, the N- series was clearly modeled on the WF- series. EDIT: Note, as I previously noted on the P&C thread, the N- series is more expansive than the WF- series. It includes wrenches (size combinations) that the WF- series did not. Whichever customer the N designates, they wanted a few more/different wrenches.