Holds the air you need to breathe underwater. They come in various sizes, but commonly used tanks are 12 or 15 litres. This is the capacity of the tank at normal pressure. The tank holds much more air than this because the air is compressed to high pressures.
Prices start about �120.
Regulator
This has two stages, the first stage connects directly to the tank valve to allow air out. This then connects via an air hose to the second stage, which is the part that goes in your mouth and delivers air to your lungs. The second stage is also called the demand valve, as it provides air as you demand it (as you breathe). All regulators are designed to supply air at the same pressure as the surrounding water, which increases the deeper you go.
Regulators from �150 to �400.
Gauges and Instruments
Usually carried as part of the regulator set, as a console containing an air contents gauge, and a depth gauge. Some consoles also feature a compass, for navigation.
Prices from �80 to about �120 with a compass.
Weights
You need to carry lead weights to make you sink. Because you are wearing a wet or dry suit, this gives you extra bouyancy in the water. The weights carried over come this.
There are other bits and pieces not detailed here, such as watches, dive computers, surface marker bouys, but we can introduce these to you later...
