Zenith Respirator automatic watch

Zenith Respirator with a very rare green dial and an original NSA-made steel bracelet. Bracelet fits a wrist about 20 cm thick. Dial has a small mark around 12 o'clock. Case has signs of age and use and the crown is original. Service history is unknown, but the watch works great. Date changes and the watch is running approximately +- 10 seconds per day.