Bowden cable for Revi EZ 42

[Frank]

Hello,
have times ne question to the bowden cable of the Revi EZ 42. which diameter does this have? completely generally, there were also verschiedne bowden cables? and how did these look? in the picture this course looks rather dark (black). Perhaps are there of it sgar Air Forces standard sheet? Thanks for the assistance
Greeting Frank
Source: German airplane cockpit of Merrick