Then, just to add more confusion, there are BCs that are a combination or hybrid of both.
For my own style of diving I’ve found that a compact wing holds me in the best position under water, so I was interested when distributor Suunto Diving UK asked if I would like to test the latest from Czech-based dive-kit manufacturer Finnsub.
I was sent a Fly 13D Rescue wing with a comfort harness and aluminium backplate.

The Design
The Fly 13D Rescue wing is designed to take only a single cylinder. With a bladder shaped like a doughnut, it has an internal capacity of 13 litres, offering 13.8kg of lift.
It’s made from welded TPU-coated 500 denier Cordura, and sits inside a zipped outer shell constructed from 2000 denier Cordura, with a high-quality corrugated inflator set on the left-hand side. The inflator has an integral shoulder pull-dump.
A further exhaust valve is set at the bottom inside-left edge of the wing and, combined, these provide three options for expelling air.
The low-pressure inflator head has stainless-steel buttons and components that add a certain amount of “heft” to stop it floating, aided by a bungee-keeper set on the harness.
Heavy-duty YKK nylon zips allow access for bladder maintenance or replacement via the top and centre of the wing.

Twin cam-bands are located in the centre section of the doughnut for securely attaching the single tank. These have rubber spigots to help hold it in place.
Two colour options are available, red (as tested) and black, and both versions sport good-quality embroidered graphics.

Harness Design
The Fly harness is made from the same heavy-duty Cordura as the wing, with padded shoulder-straps and a padded backplate cover.
The shoulder straps have no breaks and, along with the waist- and crotch-straps, are constructed with heavy-duty 50mm webbing.
Marine-grade stainless-steel fittings are used throughout, and include the waist-belt buckle, shoulder-strap stoppers and five large D-rings. There’s a choice of backplate material, stainless at 2.75kg or aluminium at 0.75kg.
Integrated weight-pockets sit at the hips, secured inside an outer pocket by plastic trident clips, and each will take up to 5kg.
Each weight-pocket has a stainless D-ring for attaching gauge and alternative regulators.
Again there is a choice of red or black to match your choice of wing colour. Both the wing and harness comply with current European standards and are CE-certified.

In Use
I set off for a day of wreck and drift dives off the coast, an ideal way to put this wing to the test.
The Fly 13D wing and comfort harness felt indestructible. The materials used are top quality and substantial, but there is a weight penalty to pay, with the whole package weighing in at 4.5kg.
The doughnut shape to the bladder meant that air could move to the highest point without the diver worrying about it getting trapped.
I knew exactly where this was in relation to my position at all times. The dumps are placed where they should be, and made getting rid of unwanted buoyant gas a doddle.
The integrated weights sat nicely on my hips, and the waist-belt and shoulder-straps were easy to adjust.
The use of a crotch-strap allowed the wing to sit and remain precisely where I set it, regardless of the amount of inflation.
The wing held me in my preferred slightly head-up position with ease as I finned effortlessly around the wreck. The compact and streamlined design ensured that there was minimal drag under water.
After a second dive, drifting and collecting scallops, I hit the surface an hour later to find that the weather had deteriorated, leaving me to await pick-up in relatively rough seas.
The Fly, fully inflated, kept my head above water, but only just. I had to shut down my drysuit dump-valve and add air to get enough extra lift to get my head well out of harm’s way.

The Czech Republic’s Finnsub has created a range of wings and harnesses that exude quality and look built to last; they can be mixed and matched to provide an optimal set-up.
The combination I had on test meshed seamlessly together, providing a solid platform that I found ideal for my type of recreational single-tank coldwater diving.
The slight lack of buoyancy at the surface wasn’t that big an issue, even in the choppy conditions I encountered.
However, Finnsub does have larger-capacity wings in its line-up. If the majority of your
diving is done at recreational depths in or around the UK, you really should check this little red number out.

PRICE £549
SIZES One size fits most (S-XL). XXL available
WEIGHT 6.5kg with ss backplate, 4.5kg with alloy backplate
D-RINGS Seven, 5mm stainless-steel
INTEGRATED WEIGHTS 10kg total capacity
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