This NOS chronograph is a late soviet production likely manufactured in 1990-1991 for exportation. It has the unusual straight chrono hands and the inner rotating bezel scaled in second with dots in the 0-15s quarter. The most common Sturmanskie 3133 chrono are scaled in hours and fitted with arrowed chrono hands. This model is referenced as the "pale-blue dial" on page 11, watch 19, in the Juri Levenberg's book, "Russian Watches".The case is made of chrome-plated brass as well as the crows and the pushers.
No bracelet came with the chrono, just the spring bars (18 mm) and that typical label of the Poljot factory control indicating : 14-5 "OTK-64" 27 and, hand-written on the verso : "86917 Chronograph" signed by Mr.(or Mrs) Chernokozhikh.
"SU" stands for a USSR production (the very late 1990-1991, I would say) of the 3133 movement, stamped with the Poljot crown near the balance wheel.