Bottle cap

Bottle Caps are the standard currency in the first Fallout game. In Fallout 2 regular money has been introduced and bottlecaps have been rendered useless.

Bottle caps are backed by The Hub merchants. 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 counterfeating efforts. Secondly, there is a limited number of bottle caps, which would serve to preserve their value to some degree.

The issue of some concern is that with time, number of bottle caps will decrease due to wear.

The graphics show bottle caps as having the rimmed edges pointing outward. That is most likely artist's decision to communicate the "bottlecapness" of the object to the player, as in real life the caps would tend to end up flattened, accidently or intentionally, to increase the storage space.