Zlatoust Diver
 

Some facts about the famous ultra-large Zlatoust hard hat diver's watch (caliber 191yC)

The original diver's watch was produced by the Slatoustowski Factory in the 1960s and 1970s. The case on these watches is solid stainless steel and is never decorated in any way, there was only a serial number on the caseback. The dial is always plain and never decorated with words, images or symbols.

Original pieces never have a second hand, either sweep or subsidiary, and they never were built with chronograph or even quartz movements.
 

The dial and hands are NOT radioactive. They do not contain radium.
The Soviet's converted to non-radium lumes by 1960 or so, as early or earlier than many Western watch manufacturers.

The 300 M Vostok Amphibia