The bottle is the second smallest item found in the miscellaneous category on the level editor in Happy Wheels, trailing only the soccer ball. They were added in v1.37 on May 6th, 2011.
The bottles are all made of glass, and can shatter very easily, where they will burst into little glass-like particles. There are a few frequent level types that focus on the use of bottles.
It is unknown what the bottles contain, however, the red text on the yellow bottle resembles the word "Miller", a beer brand in America.
There are four bottle types, which are green, blue, red and yellow, with the latter having a different shape to the others.
Bottles behave similarly to the "Cock Cola" bottle found in Effective Shopper's cart, except that these bottles are fully breakable, whereas hers, being made of plastic, only bursts open and spews cola.