With nice classic styling, it comes from late 1950s Odessa. This is not a locking doorknob, it is a door pull (there is no latching mechanism) functional only for opening and not securing a door, in the old style. Subtly ornate, really, look at the beauty in the details of the photos to see for yourself how wonderful it is! 

In 1913-1914, chemical experiments and research conducted by Russian chemists GS Petrov, VI Lisev and KI Tarasov were completed successfully - a synthetic plastic was obtained, which was called "carbolite", similar to "bakelite".

Carbolite has very valuable properties: it is chemically resistant to water, air, oils, many acids, has elasticity and, most importantly, is an excellent dielectric, easy to machine. All this ensured the widespread use of plastic "carbolite" in industry.  

Material: Carbolite
Condition: Very good vintage quality, suitable for modern usage. See photos for details.
Dimensions: Knob stands out 4 cm from base to top. Minimum door width of 3 cm (1.2") to about 3.5 cm (1.38").
Years Made: Our estimate is late 1950s, early 1960s 
Weight: 97g