
This item is no longer available.
Here are Similar First & Second Stages:
The Auto-Closure Device (ACD) is a unique feature of the Aqualung Leg3nd MBS Regulator that prevents water or silt from entering the first stage of the regulator, ensuring the internal components stay clean and dry.
The Master Breathing System (MBS) is a revolutionary feature that allows divers to easily control their breathing comfort. It controls both the direction of air, altering the venturi effect, and the opening effort.
The Aqualung Leg3nd MBS Regulator has three anti-freeze properties: an integrated dry chamber, deep ribs for heat exchange, and a new over-molded cap to delay ice formation. These features make it perform exceptionally well in cold-water environments.
The Leg3nd Supreme Octopus is a high-visibility, yellow version of the Leg3nd second stage. It is pneumatically balanced for smooth, easy breathing and features a venturi switch to prevent free-flow at the surface.
The Aqua Flex hoses are lightweight, pliable braided hoses attached to both the Leg3nd MBS Regulator and the Leg3nd Supreme Octopus. They eliminate any tugging on the mouthpiece, enhancing comfort and ease of use during dives.
Review Summary
2024-05-07T08:12:00
The regulator works well, but Aqua Lung support and customer service has been a disaster lately. Simply put, the regulator service kits are not readily available at local dive shops and Aqua Lung will not provide an estimated date of availability. I've been waiting six months for a service kit and Aqua Lung has not been responsive to my communications. I would avoid Aqua Lung entirely until they sort through their ownership/liquidity issues.
Harold D.
2023-12-15T02:57:35
Great easy breathing
Scott I.
2020-10-20T08:13:18
Leisure pro service was top notch. Love this regulator, easy adjustment, effortless breathing.
THOMAS M.
Balanced Diaphragm
Four, 3/8" UNF Thread
Two, 7/16 UNF Thread
Primary:
Inhalation Effort
Dive/Pre-Dive Venturi (Free Flow) Knob
Octopus:
Dive/Pre-Dive Venturi (Free Flow) Knob
Yes, Up to 40% O2
Pneumatically Balanced Downstream Demand Valve
First Stage: Chrome Plated Brass
Second Stages: Techno-Polymer, Polyurethane, Silicone
Primary: 29" (73.7cm)
Octopus: 39" (99cm)
3/8"
Primary: Not Specified by Manufacturer
Octopus: 7.4 oz (210g)
Happy
By Scott I.
Great easy breathing

The first inhalation under water is the start of a new adventure. The revolutionary combination of Venturi effect and inhalation effort adjustment is natural and intuitive. Aqualung's Master Breathing System allows divers to control both in one simple rotation. All depths, all conditions, all dives - MBS will adapt.
The Leg3nd Octopus provides the same great performance as the Leg3nd primary second stage.
Auto Balanced
Progressive increase of the working pressure to maintain optimum breathing efforts: Depending on the diver's depth, the working pressure of the first stage is automatically elevated to counteract the increased breathing air density
Auto Closure Device (ACD)
When the first stage is not connected to a cylinder valve, (ACD) keeps the inlet shut to protect the first stage internal parts from contamination and corrosive water
Exceptional Cold-Water Performance
The LEG3ND's integrated dry chamber keeps inner components clean and dry by isolating them from the outside environment. Deep ribs create a large heat exchange surface that helps prevent ice forming.
HP/MP Ports
2 HP ports (7/16”) and 4 MP ports (3/8”), perfectly oriented for optimal hose positioning

New Front Cover Opening Channels
Allow water to flow sideways over the diaphragm. Prevents freeflows when diving in stronger currents. Reduces peak inspiratory flow by 20%.
Overmolded Air Purge
Wide surface area makes regulator purging easier.
Purge depth controller optimizes air flow with minimal effort.
Patented Comfobit Mouthpiece
Reduces jaw fatigue and secures the second stage more comfortably.
Aqua Flex Hose
Felxible and lightweight Aqua Flex hose with dual protectors.
Air Channel Deflector
Directs the air flow evenly during the inhalation phase. Streamlined bi-material deflector lowers the exhalation effort.
Leg3nd Octopus
Includes 1m yellow hose and yellow front cover making it easy to locate in an emergency

This is for the passionate, the explorers for whom diving is more than a sport, it is a state of mind. Here is the third generation of Legend. The most advanced, innovative and ergonomic generation of regulators ever created. These masterpieces of engineering mark the plunge into a new way of discovering by ensuring the highest breathing comfort whether you are exploring in cold or warm water.
Aqualung is synonymous with the modern scuba regulator. Over 70 years of innovation have gone into making scuba regulators that are safer and easier to use than others on the market. An Aqualung scuba regulator offers you comfort, ease of breathing, control and peak performance. Aqualung and the scuba regulator share a rich history, and now is your chance to play a part. Choose the right scuba regulator to ensure your next dive is comfortable and safe. Aqualung has developed diving regulators built for new and experienced divers, as well as for a range of diving conditions.
Aqualung's premier and iconic line of Legend regulators feature an overbalanced diaphragm designed to provide excellent breathing performance. The Leg3nd range features premium engineering, with such features as Aqualungs, unique Auto-Closure Device (ACD) and the revolutionary Master Breathing System (MBS) for simple breathing comfort control. With the ACD, divers don't have to worry that water or silt will enter the first stage. Since 1943, Aqualung has been the expert in scuba regulators. Now you can carry on the spirit of that first dive with an Aqualung dive regulator that will perfectly suit your diving needs. If you want high-performance features and ease of breathing the Leg3nd MBS is the regulator for you.
Auto Closure Device (ACD) - keeps corrosive water out of the first stage inlet by automatically closing as the Legend is removed from the cylinder valve. This prevents internal lubrication from washing away. Safer for elevated percentages of oxygen. Unique over-balanced, diaphragm design results in superior performance at depth. 2 HP ports and 4 MP ports are angled for optimum hose routing. An environmental dry system keeps water out of the main spring chamber thus preventing ice buildup and keeping silt and contamination out. Available in yoke connector. Compatible with up to 40% O2 right out of the box.
Exceptional cold-water performance is achieved by modernizing Aqualung's three anti-freeze properties: 1. Where there is no moisture, there is no ice: The Leg3nd's integrated dry chamber keeps inner components clean and dry by isolating them from the outside environment. 2. Deep ribs create a large heat exchange surface area that helps prevent ice forming on the mechanism (+30% vs Glacia/+70% vs Legend 2) 3. The new over-molded cap delays ice forming over the external diaphragm. Ergonomically shaped yoke screw made of a bi-material soft grip surface provides a better hold when installing or removing the first stage - especially with cold hands.
Pneumatically balanced second stage results in smooth, easy breathing. Master Breathing System (MBS) - The MBS is a new, simple and effective way to adjust the breathing performance of your Legend MBS. The MBS controls two functions at one time. It controls the direction of air, which alters the venturi effect, as well as changes the opening effort. One control two functions, it doesn't get easier. New front cover opening channels allow water to flow sideways over the diaphragm. Radial openings to prevent free-flows when diving in strong currents. Openings widened to reduce peak inspiratory flow by an impressive 20%. New over-molded exhaust cover made of elastomer with a soft touch effect. Over-molded air purge. Wide surface area makes regulator purge easier. Purge depth controller optimizes air flow with minimum effort. Patented Comfo Bite mouthpiece virtually eliminates jaw-fatigue and secures the second stage more comfortably. Detachable and reusable mouthpiece clamp allows a quick and simple tool-free mouthpiece change without plastic waste. The enlarged heat exchanger (patented) which surrounds the valve mechanism, dissipates the cold caused by gas expansion while drawing in the warmth of the ambient water. The ergonomic exhaust tee channels the exhaust bubbles out of your field of vision. The design also contributes to a reduction in exhalation effort. Air Chamber deflector. Directs the air flow evenly during the inhalation phase. Streamlined bi-material deflector lowers the exhalation effort. Attached to a 29" (73.7cm) braided Aqua Flex hose. These hoses are lightweight and extremely pliable which eliminates any tugging on the mouthpiece and come with dual protectors. The regulator comes with an owner's manual.
To compliment the Leg3nd regulator family, Aqualung created the Leg3nd Supreme Octopus. This high-visibility, yellow version of the Leg3nd second stage is ideal to complete your system. Pneumatically-balanced second stage results in smooth, easy breathing. A venturi switch helps prevent free-flow at the surface and when the regulator is out of the diver's mouth. The opening effort is pre-set in a fixed position so the diver doesn't have to worry about adjusting the regulator during the dive. The silicone mouthpiece with ergonomic bite wings and comfort. A heat exchanger (patented) which surrounds the valve mechanism, dissipates the cold caused by gas expansion while drawing in the warmth of the ambient water. Excellent cold-water performance due to highly efficient heat exchanger surrounding the valve.
The ergonomic exhaust tee channels the exhaust bubbles out of your field of vision. The design also contributes to a reduction in exhalation effort. Attached to a 39" (99cm) yellow high visibility braided Aqua Flex hose. These hoses are lightweight and extremely pliable which eliminates any tugging on the mouthpiece. Regulator has high-visibility yellow purge cover and accent pieces. Like the primary the Leg3nd Supreme Octopus is compatible with up to 40% O2 right out of the box.
https://us.aqualung.com/en/warranty-policy.html
800-775-3483