Red "n" question

Hello everyone,

I am not sure if this has been discussed before,but I don't find information about it. Some early Soviet lenes has this red'n'(P) in Russian on the front ring. What is the meaning of the "n"? Does it mean "coated", or something else such as 'german lens elements'?

Many thanks for your kind reply in advance.

Kievuser

Yea I think it's Russian "P" - Prosvetlenniy - coated.. I may be mistaken though..

This is correct, it is for Prosvetlennyi, Coated