A backrest for a scuba diver comprising a shaped plate supporting at least one air cylinder, at least a first strap comprising an upper right portion configured to fit around the scuba diver's right shoulder, an upper left portion configured to fit around the scuba diver's left shoulder and a lower portion configured to fit around the scuba diver's abdomen, wherein the shaped plate has a first right slide-through element and a first left slide-through element adapted to connect the upper right portion and the upper left portion, respectively, to the lower portion of the first strap, at least one weight pocket constrained to the lower portion of the first strap, wherein there is provided an anti-torsion means connecting the at least one weight pocket to the shaped plate and configured to oppose the torsion of the first strap in proximity to at least one of the first slide-through elements.

The buoyancy control device for scuba diving comprises an air bladder, a harness comprising at least two shoulder straps and an abdominal strap made up of two abdominal half-straps, a backrest provided with first slots engaged by the abdominal half-straps, second slots engaged by at least one retaining strap for retaining at least one air cylinder, one or more third slots engaged by the two shoulder straps, and one or more fourth slots engaged by corresponding straps for connecting the backrest to the air bladder.

An underwater recreation system for diving instruction and method of its use. The method includes providing a series of learning steps with diving techniques and instructions to practice at incrementally deeper depths and providing a surface floating depth limitation device that restricts the learning user to the particular maximum depth of their learning step. The apparatus for carrying out the method of diving instruction includes a surface floating depth limitation device with the means to connect to the breathing hose of a surface supplied air supply.

A buoyancy control device having a back panel and including at least one flotation bladder, which at least one flotation bladder is configured with the device for controllable inflation and deflation, and connected thereto a harness arrangement for securing the device to a body of a user, the device having a cylinder-mounting mechanism arranged to enable front or side mounting of at least one breathable gas cylinder is useful for snorkeling and diving or repeated diving from snorkeling. A particularly preferred configuration provides a lightweight device of less than 5 kg and an apparatus of no more than 10 kg whereby carriage to and from snorkeling and/or diving location is simplified.

A back pack cinch for a strap securing a breathing tank, and an associated buoyancy compensation device worn by a driver are provided. The back pack cinch includes a cinch body. A cover is rotatably mounted to the cinch body. The cover has an open position and a closed position. The cover in the closed position is configured to tension a strap. A tab is rotatably mounted to the cinch body. The tab has an open position and a closed position. In the closed position, a portion of the strap is pressed against the serrated bearing surface by the tab to hold the portion of the strap in a fixed position.

A buoyancy control device having a back panel and including at least one flotation bladder, which at least one flotation bladder is configured with the device for controllable inflation and deflation, and connected thereto a harness arrangement for securing the device to a body of a user, the device having a cylinder-mounting mechanism arranged to enable front or side mounting of at least one breathable gas cylinder is useful for snorkeling and diving or repeated diving from snorkeling. A particularly preferred configuration provides a lightweight device of less than 5 kg and an apparatus of no more than 10 kg whereby carriage to and from snorkeling and/or diving location is simplified.

In one aspect, an embodiment of the invention provides a back pack cinch for a strap securing a breathing tank to a buoyancy compensation device worn by a diver. The back pack cinch includes a cinch body. A cover is rotatably mounted to the cinch body. The cover has an open position and a closed position. The cover in the closed position is configured to tension a strap. A tab is rotatably mounted to the cinch body. The tab has an open position and a closed position. In the closed position, a portion of the strap is pressed against the serrated bearing surface by the tab to hold the portion of the strap in a fixed position.

A device to facilitate weight operation in a Buoyancy Control Device (BCD) is described. The device may include a tubular body made from waterproof fabrics. The tubular body may have an exterior, a top opening, and a bottom opening. The device may include a semi-rigid tab and a pair of fastening assemblies attached to the exterior of the tubular body. The top opening may have boning that supports the top opening in an open state. The top end of the semi-rigid tab is fixed to the exterior and is close to the top opening of the tubular body, the bottom end of the semi-rigid tab is in contact with the exterior as a result of a rigidity of the semi-rigid tab. The pair of fastening assemblies are positioned on opposite sides of the semi-rigid tab.

A backrest for a scuba diver comprising a shaped plate supporting at least one air cylinder, at least a first strap comprising an upper right portion configured to fit around the scuba diver's right shoulder, an upper left portion configured to fit around the scuba diver's left shoulder and a lower portion configured to fit around the scuba diver's abdomen, wherein the shaped plate has a first right slide-through element and a first left slide-through element adapted to connect the upper right portion and the upper left portion, respectively, to the lower portion of the first strap, at least one weight pocket constrained to the lower portion of the first strap, wherein there is provided an anti-torsion means connecting the at least one weight pocket to the shaped plate and configured to oppose the torsion of the first strap in proximity to at least one of the first slide-through elements.

A device for releasably connecting a first element with a second element includes a male element connectable to one end of the first element, and a female element connectable to one end of the second element such that the male and female element pass from a disengagement condition to a mutual engagement condition. A slider activates and deactivates engagement and is engaged to the male element such to slide along the axis of insertion of the male element inside the female element. The relative motion between the activation/deactivation slider and the male element is transmitted to first removable locking members, belonging to the male element and cooperating with corresponding second locking members belonging to the female element, such to pass from a stable locking condition to a stable release condition of the male and female elements via a movement of the slider along the axis of insertion.