I recently received this flag as a gift but I am completely stumped as to what it is (the person who gifted it to me does not know either). The flag appears to be from this eBay listing and is simply labeled as F-1936-B. I have tried reverse image searching and searching for terms such as “white stripe USSR flag” but have found nothing.
This seems to be some variant of military flag, since only there the H&S could be white, compare with naval jack or the famous victory flag. The design of H&S is also from the time of great build up of Red Army in 30’s and 40’s