Hi,
I'm not sure, but i believe this sub could be a "modern" WWI or pre-war US Holland A class sub (overhaul shape looks like early XXth century Holland submarines : have a look on the restored one preserved at Gosport , England).
I said "modern" because of the conning tower : early Holland class subs had only a very little and basic one, and yours is very improved.
Secondly, look at the rear end of this sub : it looks like the incomming WWI Class S (and early WWII, for training purposes).
Is this right ?
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