Altimeter, Sensitive, USSR
Here is a Cold War era Sensitive Altimeter as used in aircraft of the former USSR. From browsing cockpit photos of USSR aircraft on the internet, it is similar in appearance to the altimeter used in the fighters MiG 27, MiG 29, and SU-27 (see images of MiG 29 and SU-27 showing the location of the altimeter).
This altimeter has 2 pointers, long and short, affixed at the center of the indicator, and then a small triangular index pointer which traverses the perimeter of the inner scale. The altimeter is adjusted for barometric pressure by turning knob in the left corner to the desired pressure shown in the small window at the 6 o'clock position.
The indicator is in exceptional condition cosmetically. The knob turns easily and rotates the pressure scale as it should. Measures ~3.25 inches diameter and ~4 inches long.