The essential instruments that a diver will refer to throughout the dive are:
Some divers prefer to bring these instruments together on a console or instrument panel. It is not difficult to make a panel to which one's instruments can be attached and the panel can then be secured by a cord. If a commercially manufactured console is purchased, it will probably be designed to take the instruments offered by that particular manufacturer and may or may not accept those instruments that the diver already has.
One of the most important instruments the diver needs to carry is a cylinder pressure gauge. This gauge allows the diver to monitor the pressure of air in the diving cylinder, most regulators have a pressure gauge fitted onto a high pressure tube and connected to the high pressure side of the regulator. This is referred to as the contents gauge, although it measures pressure rather than volume. This device allows the diver to plan his dive. He can check that he has enough air to start the dive and decide when the air is reduced sufficiently for the dive to be terminated.
