A buoyancy compensator bladder includes an air cell, a connector, a low-pressure inflator (LPI), and at least one over pressure valve. The LPI which inflates and deflates the air cell is positioned on an outer surface of the air cell. As a result, when the fully assembled buoyancy compensator is equipped by a diver, the LPI runs from behind the diver's torso and under their armpit. This results in the inflator head which is part of the LPI to be disposed on the front of the diver's chest during back mount or side mount diving. This structure allows the bladder to be easily used for either back mount or side mount diving. The bladder may further be equipped with auxiliary/non-essential devices such as wight pockets/pouches.

A handheld underwater aircraft includes a battery compartment (12) and propellers. There are at least two propellers, which are symmetrically distributed on both sides of the battery compartment (12), and are connected to the battery compartment (12). A special design with axes of the propellers being unparallel with an axis of the battery compartment (12) is adopted, and unparallel included angles make component forces generated by the various propellers in a direction of motion of a non-underwater aircraft offset each other, and enable the underwater aircraft to maintain balanced and forward-forward motion. The design with the axes of the propellers being unparallel with the axis of the battery compartment (12) leads to a little power loss, but avoids a larger power loss caused by the impact of water on the human body, thereby comprehensively improving the thrust of the underwater aircraft in use.

A handheld underwater aircraft includes a battery compartment (12) and propellers. There are at least two propellers, which are symmetrically distributed on both sides of the battery compartment (12), and are connected to the battery compartment (12). A special design with axes of the propellers being unparallel with an axis of the battery compartment (12) is adopted, and unparallel included angles make component forces generated by the various propellers in a direction of motion of a non-underwater aircraft offset each other, and enable the underwater aircraft to maintain balanced and forward-forward motion. The design with the axes of the propellers being unparallel with the axis of the battery compartment (12) leads to a little power loss, but avoids a larger power loss caused by the impact of water on the human body, thereby comprehensively improving the thrust of the underwater aircraft in use.

An apparatus comprising one or more propulsion units that are operable to help propel a user in water. The propulsion units are battery operated, such as with a rechargeable battery, and are selectively operable to create a propulsion force in water. The propulsion force propels the apparatus in water. A person wearing the apparatus, such as in the form of a vest, is propelled in water with the apparatus.

An apparatus comprising one or more propulsion units that are operable to help propel a user in water. The propulsion units are battery operated, such as with a rechargeable battery, and are selectively operable to create a propulsion force in water. The propulsion force propels the apparatus in water. A person wearing the apparatus, such as in the form of a vest, is propelled in water with the apparatus.

Therapy gas delivery systems that provide run-time-to-empty information to a user of the system and methods for administering therapeutic gas to a patient. The therapeutic gas delivery system may include a gas pressure sensor attachable to a therapeutic gas source that communicates therapeutic gas pressure data to a therapeutic gas delivery system controller, a gas temperature sensor positioned to measure gas temperature in the therapeutic gas source that communicates therapeutic gas temperature data to the therapeutic gas delivery system controller, at least one flow controller that communicates therapeutic gas flow rate data to the therapeutic gas delivery system controller, at least one flow sensor that communicates flow rate data to the therapeutic gas delivery system controller, and at least one display that communicates run-time-to-empty to a user of the therapeutic gas delivery system. The therapeutic gas delivery system controller of the system includes a processor that executes an algorithm to calculate the run-time-to-empty from the data received from the gas pressure sensor, temperature sensor, flow controller and flow sensor, and directs the result to the display.

Therapy gas delivery systems that provide run-time-to-empty information to a user of the system and methods for administering therapeutic gas to a patient. The therapeutic gas delivery system may include a gas pressure sensor attachable to a therapeutic gas source that communicates therapeutic gas pressure data to a therapeutic gas delivery system controller, a gas temperature sensor positioned to measure gas temperature in the therapeutic gas source that communicates therapeutic gas temperature data to the therapeutic gas delivery system controller, at least one flow controller that communicates therapeutic gas flow rate data to the therapeutic gas delivery system controller, at least one flow sensor that communicates flow rate data to the therapeutic gas delivery system controller, and at least one display that communicates run-time-to-empty to a user of the therapeutic gas delivery system. The therapeutic gas delivery system controller of the system includes a processor that executes an algorithm to calculate the run-time-to-empty from the data received from the gas pressure sensor, temperature sensor, flow controller and flow sensor, and directs the result to the display.

An underwater diving light with efficient waterproof performance includes a top cover, a bottom cover, a light-emitting assembly and a special-shaped light-transmitting seal. A first installation groove is formed in the top cover. A second installation groove is formed in the bottom cover. The special-shaped light-transmitting seal includes a light-transmitting waterproof part, a first installation part and a second installation part. The first installation part, the light-transmitting waterproof part and the second installation part are all annular and connected in sequence. The top cover and the bottom cover are movably connected to form a light housing. The light-emitting assembly is arranged in the light housing. The underwater diving light has the advantages of strong waterproof and moisture-proof performance, diversified luminous forms and a dazzling effect.

The present application relates to the field of underwater propeller, and more particular, to a multifunctional underwater propeller, which includes a propeller body. The propeller body is detachably connected with a handle, and a surface of the propeller body is connected with an adapter structure for detachably connecting external equipment. The adapter structure includes a connecting piece and a slide rail, and the connecting piece is in plug-in connection with the slide rail, and configured for detachably connecting the external equipment.

A backrest for scuba diving comprising a support element, a first strap strapping the support element to the diver's body and a second strap strapping an air cylinder to the support element. The support element has first slots passing the first strap and second slots passing the second strap. The first slots delimit a right portion and respectively a left portion of the first strap, independently adjustable over the right shoulder and right side and respectively over the left shoulder and left side of the diver. The support element comprises a support plate, a right angular profile having a first and second right wing, a right bracket supported by the first right wing, a left angular profile having a first and second left wing, a left bracket supported by the first left wing.