these are some of the basic things you should have for SCUBA diving, if you are taking a class (recommended) most of the equipment should be provided for you.
Air cylinder- carries compressed oxygen for breathing, usually made of aluminum or steel.
Regulator- reduces the pressure of the oxygen in the air tank to normal, breathable pressure
Mask- allows you to see clearly underwater, should be made of scratch proof plastic or glass, and be easily adjusted.
Fins- allow easy propulsion through the water, usually warn with neoprene boots.
Weight belt- compensates for the buoyant effect of the air cylinder and wet suit (especially with an aluminum tank)
BC- or buoyancy compensator, allows you to control your buoyancy by adding or removing air from an essentially balloon filled vest.
Snorkel- basic tube that allows breathing on the surface in choppy water without use of the regulator.
Secondary air source- either a second regulator or an emergency air cylinder is very important to have in case of emergency.
Wet/dry suit- these suits will keep your body warmer, for longer, even in very cold water (dry suit) make sure your's fits very well
Dive log- should come with US Navy dive tables (if in US), very important for planning dives
Dive Console/Computer- used to figure out depth, directional heading, and other vital information about your dive.
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