This is the only example I have ever seen since last May when I began to hunt vintage Chinese watches. It might be produced in even smaller numbers than Shanghai 24 jewels military automatic(about 25,000 24j Shanghai were made betwen 1971-77). The watch was made in the late 1960's when Dongfeng brand was still used by Tianjin Watch Factory. Then in the early 1970's when Tianjin began to export watches , the brand was changed to a less revolutionay "Seagull".:-D
It could also be one of the earliest Chinese automatic watches.