Pony bottle

In scuba diving, a pony bottle refers to a small, secondary scuba cylinder that divers carry as an emergency backup or for situations where a short-duration additional air source may be needed. It is smaller in size compared to the primary scuba tank and is typically mounted on the diver’s equipment, often on the side of the main cylinder or on a separate bracket.

The pony bottle usually contains a limited amount of breathing gas, typically enough for a relatively short duration, intended for emergency ascent or sharing air with a buddy in need. Divers often use pony bottles for added safety during dives, especially in situations where a quick and controlled ascent is required.

The term “pony bottle” is derived from the smaller size of the cylinder, resembling a small companion to the larger primary scuba tank. It serves as a redundant air source, providing divers with an additional option in case of an emergency.