VINTAGE FOMO OPTEK EARLY RUSSIAN EXTINCTION LIGHT METER
The earliest light meters were called extinction meters and didn't require batteries. They worked by looking through their viewfinder at a small strip of letters that were progressively darker. The darkest letter you could just barely read was your light value. You then used the handy barrel to convert the light value to your exposure, taking into account the sensitivity of your film emulsion.
This meter is quite historically significant as it is a direct rip off copy of the Bing extinction meter which was patented in the USA during 1940 - see photo!
It was made in the USSR in the late 1940s/ 50s by Fomo and comes in beautiful condition ensconced in it's original cardboard box.