Aqualung Legend 3 MBS Regulators

The Leg3nd MBS brings two breathing adjustments together in one control. Its Master Breathing System changes Venturi assistance and inhalation effort simultaneously, while the dry-sealed, over-balanced first stage provides the foundation for warm- and cold-water use.

Features and benefits

Balanced gas delivery. The over-balanced diaphragm mechanism helps manage the supply to the second stage as diving conditions change.
Balanced second stage. The balanced valve helps maintain a consistent inhalation response.
One adjustment control. The Master Breathing System changes Venturi assistance and inhalation effort together.
Environmental protection. The sealed first-stage chamber helps keep water and contaminants away from its working mechanism.
Automatic inlet closure. The inlet closes when disconnected from the cylinder to help protect the first stage from water and debris.
Comfortable mouthpiece hold. The Comfo-Bite palate bridge helps support the second stage without a hard bite.

Setup and compatibility

Connection: DIN, Yoke. Choose the fitting that matches your cylinder valve and its pressure rating.

Technical Specs

Aqualung Legend 3 MBS Regulators technical specifications
Brand	Aqualung
Main model / configuration	Aqualung Leg3nd MBS
Product type	Regulator
Regulator type	Primary Regulator
Regulator connection	Din, Yoke
First-stage design	Over-balanced diaphragm
Second-stage design	Pneumatically balanced
High-pressure ports	2
Low / medium-pressure ports	4
Environmental sealing	Yes, permanent dry chamber
Cold-water suitability	Cold and warm water
Breathing adjustment	Master Breathing System: combined Venturi and inhalation-effort adjustment
Mouthpiece	Comfo-Bite
Technical features	De-icing heat-exchange ribs and overmoulded cap
Venturi control	Yes
Heat exchanger	Yes
Automatic inlet closure (catalogue)	ACD automatic inlet closure

Additional specifications

The Legend 3 has a unique combined adjustment that controls the inhalation effort and venturi effect automatically. The Master Breathing System is a new way to adjust the comfort on a second stage. The diver can perfectly master breathing comfort in one simple rotation. With the MBS on minimum position (only one full rotation), the spring is fully compressed and inhalation effort is about 3 mbar higher.
The cracking effort has been reduced by 20% more than the previous legend model, and this eases the breath amazingly at any depth.

Legend 3 First Stage

Auto-Closure Device Prevents corrosive water out of the first stage inlet by automatically closing as the core is removed from the cylinder valve, preventing internal lubrication from washing away and is safer for higher proportions of oxygen
Over-balanced Diaphragm Unique, over-balanced diaphragm results in superior performance at depth
HP/MP Ports and "T" Shape 2 HP ports (7/16") and 4 MP ports (3/8"), Precisely oriented streamlined hose positioning
Yoke or DIN Available in yoke (3,300psi/232 bar max.) or DIN (4,350psi/300 bar max.)
Up to EAN 40 Compatible with up to EAN 40 right out of the box

Legend 3 Second Stage

Master Breathing System Master Breathing System (MBS) gives you two breathing performance controls in one: change the opening effort and change the direction of air, which alters the Venturi effect
Pneumatically Balanced Pneumatically balanced for smooth, easy breathing
Braided Hose Attached to a 29" braided Aqua Flex hose that is lightweight and extremely pliable, eliminating strain from tugging on the mouthpiece

Based on Aqualung product information.

Type	Din, Yoke

We dispatch orders five days a week, usually within 1–3 days. Standard mainland Australian shipping is $20. Click & Collect from our Hallam store is free once your order is ready.

Large or bulky gear: additional freight charges apply on top of standard shipping: large dive bags $30; long freediving fins $15; long spearguns $20. Scuba tank freight is shown at checkout.
Rural, remote & offshore: rural means anywhere outside metropolitan areas. Carrier availability and additional charges may apply, including for island and territory destinations. Our team will contact you if an extra freight quote is needed.

The available delivery rate for your order is shown at checkout.

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We offer a 30-day exchange on most unused products within Australia when they are in saleable condition with their original packaging and accessories. Please contact us with your order number before returning an item. Change-of-mind refunds are not offered; this does not limit your rights for faulty products under Australian Consumer Law.

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FREE CLICK & COLLECT
Usually ready same day*

Select local pickup at checkout. We will email you when your order is ready. Please wait for your ready-to-collect confirmation before visiting, then bring your confirmation email and photo ID.

Collect from our Hallam store
Factory 4 / 56–60 Hallam South Rd
Hallam VIC 3803

*For items in stock at our Hallam store during opening hours, subject to order processing. Available-to-order and special-order items take longer. Collection is unavailable while the store is closed.

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Can I collect my order from the store?

Yes. Choose free local pickup at checkout and wait for your ready-to-collect email before visiting our Hallam store. Bring your confirmation and photo ID. See Click & Collect details.

How do I choose the right size?

Use the product's size chart where available and compare your measurements with the guide for that brand. Sizing varies between brands and products. If you are unsure, contact our team before ordering and we can help you choose.

How do I check availability?

Select your required options, such as colour and size, to see availability for that variation. If an item is marked “Available to order”, check the estimated dispatch information. Please contact us before ordering if you need gear by a particular date.

When will my order be dispatched?

Orders are usually dispatched within 1–3 days, subject to stock availability. Available-to-order and special-order products may take longer. Delivery time is separate from dispatch time and depends on your location and the carrier. Read our shipping information.

Can I exchange an item if it does not fit?

We offer a 30-day exchange policy on most unused products within Australia, subject to eligibility. Contact us with your order number before returning an item. Read the exchange conditions and next steps.

Can you help me choose the right gear?

Yes. Call 03 9702 3694 during store hours or email [email protected]. Tell us which product you are considering and how you plan to use it.

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