Black and Medium Gray Dye Module
The Black and Medium Gray Dye Module originally could be found on the Cartel Market, Cartel Packs or Dye Packs. Due to the random nature of Cartel Packs and Dye Packs, there is a low chance of receiving any specific dye from these packs, it is recommended to instead buy the Black and Medium Gray Dye Module from the GTN from other players.
When you use the Black and Medium Gray Dye Module, it will dye the primary dye section of your armor Black, and the secondary part of your armor Medium Gray.
All dye modules are one-use, so once you've added a Black and Medium Gray Dye Module to your armor, you will not be able to remove it and reuse it later.