Looks to me like a pin lever movement, and there is no way it has 21-jewels! Rocker bar winding behind the dial. With all the florid engraving on the back, and excessive information on the dial, this watch is masquerading as something it isn't!
Perhaps not the proudest moments of Swiss watchmaking, but not faked in any way. It is some version of Bettlach caliber EB802x. http://www.christophlorenz.de/watch/movements/e/eb/eb_8027.php?l=en I have seen other "divers watches" from the 70s using these. They are fully serviceable and possible to make run relatively precise.
If you ever see "Seagull" brand watches, they are another Chinese maker who also sends their movements to larger, more expensive watch companies. So even some of your respected brands use cheap movements.
Nothing wrong with Chinese watches I guess? I have none, but at their best I've been told they can produce decent movements. The watch in question has a Swiss movement, but also a very cheap one.
I am wearing this 1982 Constellation Manhattan. The map in the foreground shows the military operations that took place in 28 October 1940 when Italy attacked Greece:
My friend wristwatch is nothing special ... unless the wearer is Olympic champion in Beijing 2008 ... He wants my Speedmaster. I want to be Olympic champion ... If I give it to him ... I will be gold in Rio 2016? ( I don´t think so )
When I bought this 1968 Constellation years ago, I thought it was large. Now considered small. But with Cal 564, one of the best in the business