General question about the materials used to manufacture SA/NSDAP armbands

[Cyano]

Hello everyone,

Not being a specialist, while browsing this forum, I discovered that SA armbands (and probably others) can be made of different materials: wool, cotton, linen. Is there a historical reason for these different materials? What do you think are the most interesting models?

Thanks again for your feedback.

[Cyano]

As I have the option of buying one in cotton or the other in wool, I'd like to know which to choose first. Thanks for your help!