| || For an overview of bottle caps in the Fallout series of games, see Bottle cap.|
For an overview of currency in the Fallout series of games, see Currency.
This bag holds your bottle caps.”— Fallout in-game description
The Nuka-Cola bottle caps are backed by the Hub merchants in the Core Region. The reasoning for their support is that the technology to manufacture bottle caps and paint the surface has been lost in the Great War, which would greatly limit any counterfeiting efforts. Secondly, there is a limited number of bottle caps, which would serve to preserve their value to some degree.
Bottle caps are also called Hubbucks, because they originated from the Hub.
Even though the icon shows a number of caps in a bag, each is only actually a single bottle cap.