How should look the: Pilotka for Engineering Officer of the RKKA for II World War ?.

I really search on many web pages and books. And I can’t find the answer for my problem. Well the Engineering Officer Epaulets have the black endings.
So should the material star (under the officer’s star) should be black or maybe red ?.
And the endings on the top of the Pilotka, should be black or red ?.
This is my "Cerberus Maze". notcool

Help will be appreciated Yours Mario

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