Editing Diving weighting system (section)

===Fixed weights===
[[Surface-supplied diving|Surface-supplied divers]] often carry their weights securely attached to reduce the risk of accidentally dropping them during a dive and losing control of their buoyancy. These may be carried on a weight belt with a secure buckle, supported by a weight harness, connected directly to the diving safety harness, or suspended from the [[Glossary of underwater diving terminology#corselet|corselet]] of the helmet. Heavily [[Weighted shoes (diving)|weighted footwear]] may also be used to stabilise the diver in an upright position.

In addition to the weight that can be dropped easily ('ditched'), some scuba divers add additional fixed weights to their gear, either to reduce the weight placed on the belt, which can cause lower back pain, or to shift the diver's center of mass to achieve the optimum position in the water.
* '''Tank weights''' are attached to the diving cylinder to shift the center of mass backward and towards the head or feet, depending on placement.
** '''V-weights''' are long, narrow, weights which are carried in the groove between twinned cylinders. They may be carried singly or as a pair. Traditionally wedge sectioned lead castings, but also found in solid cylindrical format and as long narrow webbing weight pockets filled with shot.<ref name="Tecsysteme" /><ref name="DIRzone" />
** '''Tank trim weights''' are smaller weights , usually strapped towards the base of an aluminium cylinder to prevent it from trimming  base-upward in seawater when side- or sling-mounted,  when the gas is used up.
* '''Ankle weights''', which are typically about 1&nbsp;lb./0.5&nbsp;kg of shot, are used to counteract the positive buoyancy of [[diving suit]] leggings, made worse in drysuits by the migration of the internal bubble of air to the feet, and positively buoyant [[Swimfin|fins]]. Some divers prefer negatively buoyant fins. The additional effort needed when finning with ankle weights or heavy fins increases the diver's gas consumption.
* '''[[Backplate and wing|Metal backplates]]''' made from stainless steel, which may be used with [[Backplate and wing|wing style buoyancy compensators]], move the center of mass upward and backward. Some backplates are fitted with an additional weight, often mounted in the central channel, also called a keel weight or a p-weight.<ref name="Tecsysteme" />
* '''[[Diving cylinder|Steel diving cylinders]]''' are preferred over aluminium cylinders by some divers—particularly cold water divers who must wear a suit that increases their overall buoyancy—because of their [[Diving cylinder#Buoyancy characteristics |negative buoyancy]]. Most steel tanks stay negatively buoyant even when empty, aluminium tanks may become positively buoyant as the gas they contain is used. High-pressure (300bar) steel tanks are significantly negative.

<gallery>
Image:Aa shotbelt.jpg|Shot belt for scuba diving
Image:Aa leadshotanklets.jpg|Lead shot anklets for scuba diving
Image:Aa weightsandbelts.jpg|Diving weights and belts, showing two sorts of belt clip
Image:Weight-belt.jpg|A diving weight harness system with integrated weight pockets
File:Baudrier artisanal de chasse sous marine.jpg|Freediving weight harness for spearfishing
File:Clip-on diving weight back view DSC04182small.jpg|Clip-on trim weight on harness webbing (back view showing shock cord gripping webbing)
File:Draeger clip-on diving weight DSC03662.JPG|Draeger clip-on weight showing clip mechanism
File:Diving safety harness with weight pocketsPA268045.jpg|A diver's safety harness with removable weight pockets, used for surface-supplied diving
File:Block clip-on diving weight P6045427.JPG|Clip-on main dive weight using a belt bracket and spring clip retainer
File:Block clip-on diving weight P6045428.JPG|Clip-on main dive weight showing the belt bracket and spring clip retainer
File:Block clip-on diving weight P6045431.JPG|Clip-on monolithic block type main dive weight front view
File:Block clip-on diving weight P6045433.JPG|Clip-on monolithic block type main dive weight showing the hinged grip plate and shock cord retainer
File:Block clip-on diving weight P6045438.JPG|Clip-on monolithic block type main dive weight back view
File:Travel clip-on dive weight P6045453.JPG|Clip-on assembled main dive weight using a hinged grip plate and shock cord retainer. The support framework is designed to be lightweight for travel and can carry a wide range of standard weight types.
File:Dive weights - Tubular and rectangular shot bags and cylindrical tank weights P8160083.jpg|Dive weights - Tubular and rectangular shot bags and cylindrical tank weights
</gallery>