Got some more insulators all the way from Magnitogorsk. This one is a CD 304.5, about 9" diameter, light green somewhat crude glass.

This is a product of the Lviv Insulator Company in the Ukraine, the next photo shows their insulator symbol embossing..

http://www.energyglass.com.ua/ua/?topic=nomenclature

the other major former USSR glass insulator manufacturer was the Yuznouralsk Insulator Company in Russia, they made the ones with the "UFO inside of a C" embossing.

[IFONA CD 304.5]