DUI, the Californian manufacturer, has an enviable reputation for the quality of its drysuits, albeit that they are expensive. So whats so good about its new-to-the-market wing-style DUI Delta BC
     Size can be varied from Small to Large through the positioning of the Velcro-covered harness straps behind the removable back-cushion. These straps can be further adjusted for fit using weightbelt-style buckles behind the shoulders, as well as the normal front shoulder-strap adjustments. So one size really does fit all.
     Thats good for retailers, because it reduces the number of units needed to be held in stock. The waist-strap and the sternum-strap are equally adjustable, and there is a crotch-strap, too.
     The Delta also has a couple of small stainless-steel rings on extending bungees. These are for attaching any consoles or compasses that need to be held away from the body when in use, but need to be kept tidy when not. What else is special Not much, actually.
     The integrated-weight system has a pouch either side, held in place by a complicated interweaving of plastic wires through little fabric loops. In an emergency, you simply pull on the big yellow handles attached to these wires to release the pouches.
     However, after each dive I found myself handing up my weights into the boat one at a time. There was no way I wanted to release the pouches, having done it once and then found out how fiddly it was to reinstall them. Its not a job you want to do in a cramped RIB thats rocking and rolling.
     Equally, I stashed the weights in the pockets at the last moment, after I had donned my rig and was ready to jump into the water. It was all too complicated otherwise. So nil points for the integrated-weight system.

Unclipped and abandoned
The buoyancy cell is contained within a strongly made outer bag. It has a couple of horizontal elastic straps designed to resist it wrapping around the tank, and these can be unclipped and abandoned if the user so wishes.
     There are two cambands to keep it firmly attached to the tank. However, I found that I also had to use the loop of strap attached to the harness but passing through the wing, and tie this round the tank neck to keep it all from getting very untidy. Often these straps are relegated to being used as a hanging device, but not so in this case.
     Its nice to have some pockets for carrying items but there are none on this BC. This is not the end of the world, as there are four big stainless-steel D-rings. However, now we come to the big problem.
     All I really ask of any BC is to be able to put air into it on the way down and to let that air out of it as it expands on the way up. Not too much to ask, is it Thats what buoyancy control is about. I cant understand how any manufacturer can come to the marketplace without meeting this basic requirement.
     It really is very difficult to be comfortable with this wing-style BC under water. The top of the buoyancy cell reaches high above shoulder-level, and by letting air into this upper cushion, your upward force for buoyancy ends up behind your head while your downward force, your weights, are down by your waist. Its a guaranteed method of giving you backache.
     But wait - theres more.
     Swimming horizontally, this cushion tends to pull back over the tank, hinging away from you level with your shoulders. The first sign of trouble is when the corrugated direct-feed hose disappears upwards until its business end gets caught by the front left shoulder facing under which it passes.

Distorted inner bag
You are meant to dump air by pulling on this hose, but even once youve located it (and thats not easy), pulling on it only pulls down that part of the buoyancy cell, rather than operating the top-of-hose dump valve.
     The net result is that the air is left trapped in the upper and opposite part of the now distorted inner bag.
     It really is something of a dogs dinner. I found myself groping upwards for the direct-feed control and, after recovering it from where it had lodged, needed to pull it through and then raise the hose in the old-fashioned way, rotating my body to get the air to that part of the buoyancy cell where the hose joined.
     Its not something you want to do when handling a big camera rig in a fast-moving current and while starting to accelerate upwards in a momentary loss of control.
     I used the Delta for a weeks diving and, frankly, it was misery. I got backache, the tank seemed to roll around, very careful about ascending. Not only that, but once my diving was finished and it was time to pack up to come home, I found that the water that had inevitably entered the buoyancy cell while air was dribbled out was almost as impossible to get back down through the hose as the air had been to get out.
     There is a lower dump valve, good for venting air during fast head-down descents perhaps, but first you have to get all the water into that side of the inverted U-shape that is the wing.
     Many designers give the user a lot of inflated wing that is out of the water when at the surface, and therefore not contributing in any way to lift. At this time it cannot displace any water because it is not immersed.
     Few seem to have grasped the idea that there is little point in having any inflatable part positioned higher than the top of the shoulder straps (the Buddy Trident is a good example of how it should be done).
     There is no point in having any part of the lift higher than the mouth of the wearer, and the Delta seems to be one of the worst examples I have come across.
     Despite what people might think, its rare that I actually slate a product. But this is one of those products. DUI, please go back to the drawing board. You make some fine examples of diving kit. The Delta is not one of them.
The DUI Delta costs £418.
  • Hydrotech 01455 275030,

  • Divernet Divernet
    + One size fits all

    - Not great for buoyancy control
    - Impractical integrated weight system
    - No pockets
    - Not cheap