This regulator is a V2 by Nemrod of Spain.  All the first V2 regulators imported to the USA were marked Snark III.  The main reason for the name change was to avoid the political gaff of the regulator having the same name as Hitler's V2 vengance weapon launched against London during WWII.  This particular model was most likely made in the mid to late 50s.      The hose assembly on this regulator is a very rare surviving example of the one hose assembly similar to the early Aqua Lungs.  These hoses are black but earlier models had blue or red hoses that perished very easily.  This improved black version held up much better and could be found on the V2(Snark III) and the earlier Asteria.

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