Aqua Lung Dimension BCD

The Aqua Lung Dimension is a thoughtfully engineered back-inflate BCD that combines Aqua Lung's best proprietary systems into a comfortable, streamlined package suited to divers who value trim and simplicity.

## Overview

Aqua Lung's Dimension sits in the upper tier of the recreational BCD market, and at $700 AUD it competes directly with the likes of the ScubaPro Hydros Pro and the Cressi Patrol. What distinguishes it is the convergence of three Aqua Lung-specific technologies: the i3 one-touch inflation system, the SureLock II mechanical weight release, and the Monoprene harness material. Together, these aim to simplify buoyancy management and weight handling while delivering the streamlined profile that back-inflate BCDs are known for.

The i3 system replaces the traditional inflator hose and buttons with a single lever on the left shoulder that controls inflation, deflation, and oral inflation through one hand. It is Aqua Lung's answer to the complaint that traditional BCD controls are unnecessarily complex, and after extensive testing across Australian conditions it largely delivers on that promise — though it requires a period of adjustment for divers accustomed to conventional controls.

In the water, the Dimension performs confidently across the range of Australian diving. From buoyant tropical reef dives on the Great Barrier Reef requiring careful weight management, to cold-water dives in South Australia where the back-inflate design helps maintain horizontal trim under thicker exposure suits, the Dimension adapts well. Compared to the ScubaPro Hydros Pro at a similar price, the Dimension trades the Hydros' modularity for the i3 system's simplicity. Against the more affordable Cressi Patrol back-inflate at around $500, the Dimension justifies its premium through superior build quality and the genuinely useful SureLock II weight system.

## Key Features

- **i3 one-touch inflation system**: Single lever controls inflate, deflate, and oral inflate, replacing the traditional corrugated hose and dual-button inflator - **SureLock II integrated weight system**: Mechanical weight release with audible confirmation click, rated to hold up to 4.5 kg per pocket - **Monoprene harness**: Proprietary material that combines the flexibility of neoprene with the durability of nylon, conforming to body shape - **Back-inflate bladder**: Rear-mounted air cell promotes horizontal trim and streamlined profile in the water - **Stainless steel D-rings**: Multiple attachment points for accessories, lights, and reels - **Wrap-around air cell**: Provides lift of approximately 13.6 kg (30 lbs) depending on size, with even distribution - **Padded backplate**: Integrated padding for comfort during surface intervals and boat rides - **Quick-release chest and waist buckles**: Tool-free adjustment for rapid donning and doffing

## The Good

- **The i3 system genuinely simplifies buoyancy control once you learn it**: After an initial adjustment period of three to four dives, the single-lever operation becomes intuitive. One push inflates, pull deflates, and the oral inflate function is integrated into the same control. During a week of diving at Osprey Reef, the i3 lever became second nature and switching back to a traditional inflator felt clunky by comparison - **SureLock II weight system is the best integrated weight release in the business**: The mechanical click when weights lock into place provides audible and tactile confirmation that your weights are secure. The release pull is smooth and reliable, and the SureLock II has an excellent safety record. During emergency ascent drills, the weight ditching was fast and clean every time - **Back-inflate design delivers excellent trim**: The rear-mounted bladder keeps the centre of buoyancy behind you, promoting a natural horizontal position in the water. For photographers who need stable positioning, or divers working on their trim for wreck penetrations, this design pays dividends. The effect is particularly noticeable compared to jacket-style BCDs - **Monoprene harness is remarkably comfortable**: The harness material conforms to your torso over time, creating a custom-like fit that distributes weight evenly. On full-day dive trips at the Poor Knights Islands (for Kiwi crossover trips) or extended surface intervals at the Ribbon Reefs, the Dimension remains comfortable when many BCDs start to chafe - **Build quality reflects Aqua Lung's manufacturing standards**: Stitching, material quality, and hardware all feel premium. After a year of regular salt water use including some rough treatment on charter boats, the Dimension shows normal wear without any structural concerns - **Streamlined profile reduces drag**: The back-inflate design with minimal frontal bulk means less resistance in the water, which translates to lower air consumption and less fatigue on longer dives

## The Bad

- **i3 system creates a learning curve**: Divers switching from traditional inflator controls will need several dives to retrain their muscle memory. The i3 lever operates differently from anything else on the market, and in the first few dives there is a real risk of inflating when you mean to deflate. Training dives in shallow, controlled conditions are strongly recommended before taking it to depth - **Incompatible with standard inflator hoses**: The i3 system uses a proprietary connection. If the i3 mechanism fails during a dive, you cannot simply swap in a standard inflator hose as a field repair. This is a single point of failure that makes some divers uncomfortable, though Aqua Lung's reliability record with the i3 is strong - **Surface floating position takes adjustment**: Back-inflate BCDs inherently push you face-forward on the surface when fully inflated. Divers accustomed to jacket-style BCDs that hold them upright at the surface will need to adapt their surface positioning, particularly in choppy conditions common at exposed Australian dive sites - **Price is at the upper end of the recreational range**: At $700, the Dimension is not cheap. Divers who do not value the i3 system or the SureLock II specifically may find equal diving performance from less expensive back-inflate BCDs without the proprietary features

## Verdict

The Aqua Lung Dimension is a refined BCD that rewards divers who invest the time to learn its proprietary systems. The i3 one-touch inflation genuinely simplifies buoyancy management once mastered, the SureLock II is the most confidence-inspiring integrated weight release available, and the back-inflate design delivers the trim and streamlining that experienced divers seek. The Monoprene harness adds a level of comfort that is difficult to find in competitors.

It is best suited to intermediate and advanced divers who are committed to the back-inflate philosophy and who appreciate thoughtful engineering over feature checklists. New divers should learn on conventional BCD controls first. Divers who want interchangeable components and field-serviceability may prefer the ScubaPro Hydros Pro. But for those who want a well-integrated, comfortable, and capable BCD for the long term, the Dimension earns its place at the top of the mid-range.

Star Rating: ⭐⭐⭐⭐⭐ (4.5/5)