These are not ranks. They are more like identification/security tags. I don't think they ever been established what the purpose is just a very SWU greebie to enhance costumes. I believe that one belongs to Andor. I believe the general consensus is that it is made made from a mold that was created from a master of various doo-dads. Some may be model parts and some may be just other found parts like maybe a bearing.
Here is someone's pretty interesting take on it...
This Costume Accessories item by JJIndustriesUK has 577 favorites from Etsy shoppers. Ships from United Kingdom. Listed on May 31, 2024
www.etsy.com