The leather jacket is a pre-war attire, but it is possible that Craftmens of the post-war may be making it to this day. It is constructed of tanned brahmin skin, much like leather armor. While It doesn't have much in terms of protection, there is a few things that can happen while wearing it:
Sometimes a male character wearing a leather jacket can convince the Khans that he is the Death-Hand, Garl's father, returned from the dead after Garl killed him.