Poljot 3133 era
In 1973 Poljot launched it's second chronograph movement, which got the code 3133. It was built on a Valjuox 7734 basis and very soon replaced entirely old 3017 movement. New 3133 movement didn't have column wheel so it's simpler and cheaper and in additon it also had a date complication.
Again the new chronograph movement was primarly intedned for the military use, first wacth with this movement was called Okean, and it was intended for the soviet navy. Soon it was followed by Šturmanskie, which was made for soviet aviation. First civil wacthes with this movement were only available at the end of seventies. But 3133 movement became one of the most word wide known Poljot's movement and watches with this movement were known all over the world.
Of course new chronograph was very soon taken also by the Soviet space program. But Poljot newer made any specific watch just for the space program. So all military versions were also used in the space program, for sure Okean and Šturmanskie were used by the kosmonauts in the period 1973-1994.
Okean is one of the most collectible Soviet watches. Several slight modifications were made during the production period. Mine is the version from the late eighties (movement is from 1987).
At the beginning of eithiest Poljot upgraded movement 3133 with additional complication - stop second. That movement is marked as 31659, and it also has 25 instead of 23 jewels. I have a Šturmanskie version of the watch with this movement.
As it is common in ex. soviet iconic watches, both Okean and Šturmanskie have a bunch of reeditions. I have one Okean from Volmax made in 2011 and one Šturmanskie, also made by Volmax Šturmanskie. Last reeditions of both models were issued in 2020 but at the time being I don't own them.