Zhongshan 钟山 Nanjing Watch Factory.
From the wonderful Chinese Watch Wiki:
Design features
The SN2 has a number of unique design features not seen in other Chinese movements, intended to reduce costs and facilitate easy maintenance:
- The wheel train bridge and winding bridge are a single plate
- The mainspring barrel is uncovered
- The keyless works uses a single part where standard designs use several parts
- The screws have extra-large heads and the different kinds of screw have visibly different shapes
Great power reserve, robust and easily accurate enough for daily use.
Solid stainless cases and backs, too.
Curator: Alberta Museum of Chinese Horology in Peace River; Member: China Horologe Association; Chief Expert: China Watch Overseas Working Committee (CWOWC); Sino-Canadian Horological Cultural Affairs...
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