The Design
The Quantum is a traditional, front-adjustable, jacket-style BC. The main body is constructed from tough Cordura, with a bladder that’s a new concept for Mares BCs. It’s designed to deliver a high lift-capacity while maintaining a low profile at the sides to allow optimum mobility and freedom of movement.
A newly designed and patented integrated-weight set-up called the Slide and Lock-System (SLS) has been included. This features an indicator to allow the user and buddy to instantly confirm that the integrated weight-pouches are locked and secure, and there are two further integrated pockets set either side of the tank position for trim-weights.
Two large cargo-pockets are made with a tough, elastic and abrasion-resistant material the maker calls Supratek. The elastic properties allow the pockets to compress around their contents and maintain a low profile. Access is via front zippers.
The Quantum harness includes swivel-joints at the shoulders and well-placed D-rings for attaching ancillaries. Hose tunnels are provided for streamlined gauge and octopus use, along with grommets for knife-attachment.
The Quantum has a padded mono backplate that’s designed to take both single- and twin-tank set-ups, and is finished in all-black, with micro-injected cosmetic labels.

In Use
I used solid block-weights in the integrated SLS system. They sat inside zipped pouches and were secured by sliding them along the internally fitted tunnels either side of the waist-belt.
Solid handles on the pouch make the attachment process easy, and a firm push of the centre red section then locked the system positively into position.
When this had been done, the red Unlocked icon on the side changed to a white Locked version. It’s not big but it’s easy to see, and gave an instant indication of the state of play.
Attaching hoses, gauges and octo was easy, thanks to the excellent placement of the D-rings. There is even a small plastic ring strategically placed on the right-hand shoulder harness to attach a console via a lanyard, and this puts the console within line of sight when diving in a horizontal position.
The whole set-up was extremely comfortable to dive in. Virtually everything is padded, and the swivel-buckles on the chest allowed the harness to nestle without being restrictive.
The sternum-strap is positioned quite high, so it didn’t interfere with my drysuit inlet, and a clever feature is that it adjusts only on the left, so the loose end of the strap doesn’t interfere with the shoulder-dump toggle.
The backplate has an integrated carry-handle at the top, and allowed me to manhandle the whole scuba unit easily when on land.
Under water the Quantum sat perfectly on my drysuit-clad torso. Padded kidney sections featuring a textured surface meant that it didn’t slip and ride up my body when the bladder was fully inflated.
The BC held me in my preferred orientation under water and, as is the case with most jacket-style BCs, put me in an armchair position at the surface.
Gas migrated well around the air-cell and was easy to discharge from any of the three dump-valves, whatever position I was in at the time.
I didn’t use the knife-attachment grommets or the hose-tunnels so I can’t comment on them, but I did put a spare mask in one of the pockets and a DSMB and spool in the other.
The zippers were easy to find, and slid downwards to open.
The elasticated Supratek held the contents in position until I removed them, and would no doubt help prevent the loss of contents should you forget to zip up the pockets.

Conclusion
The Quantum appears to be the culmination of years of experience from the clever Italians who brought the world’s best-ever fins to the diving world. The little design details all add up to make this “feature-rich” BC functional and extremely comfortable.
I loved the weight-locking system, which is possibly the best I’ve seen. It pushed into place with a positive click and then showed anyone who cared to look that it was locked and secure.
The only downside is the Quantum’s weight. I’m being picky here, but for travelling divers it is a bit on the heavy side at 4.32kg (size M). However, its performance and comfort were good enough for me to consider leaving unwanted underwear, toiletries and T-shirts at home to make the baggage-weights and take it abroad with me.

Specs
PRICE: £314
INTEGRATED WEIGHTS: Yes, SLS
TRIM WEIGHT POCKETS: Yes
TANK CONNECTION: Single camband
SIZES: S, M, L, XL, XXL
WEIGHT: 4.23kg (size M)
D-RINGS: Six large, five small
CONTACT: www.mares.com
DIVER GUIDE: 9/10

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