Appeared in DIVER September 2008

John John Bantin has been a full-time professional diving writer and underwater photographer since 1990. He makes around 300 dives each year testing diving equipment.


NOT SO LONG AGO, I remember wearing a drysuit undersuit during a cool winter evening in Sharm el Sheikh because I thought it looked chic. It didnt. I looked as if I had just been down an inspection pit and serviced my car.
However, whereas most undersuits used to make you look as if you were wearing a duvet, this one must have impressed me by actually having some shape to it.
When those Swiss microfibre versions arrived, I got myself a bright yellow one. I was careful not to use it as casual wear, but even my Tellytubby-watching friends began calling me Lala.
Then some undersuit designer came up with the concept of making a garment that would not subject the wearer to ridicule if he chose to climb out of his drysuit and go to the pub in what he wore beneath it.

The Fourth Element SubXero two-piece suit comes into this category. In fact, one could be forgiven for thinking that the top part was quite an attractive jacket.
Its outer layer is waterproof and windproof, which makes it ideally suited to a typical British day at the seaside. The lower half comprises a salopette in the style favoured by skiers.
I wouldnt be surprised to see snowboarders so attired this winter in the European Alps. This salopette pulls up over the head and chest, fastens with a long zip and is given shape at the waist by a built-in belt.
There is a convenient flap for gentlemen, and zipped pockets that accommodate those accessories used by ladies.
These pockets are well thought-out, because they are vented and leaving them unzipped under your drysuit will help with evacuating air from the suit when the time comes. It will probably appeal to those who eat a lot of beans washed down with plenty of ale, too.
There are also hip pockets, which I presume are for spanners if youre doing an oil-change between dives.
The ankles come with Velcro-covered straps. This helps when it comes to squeezing them down the legs of your drysuit.
The same is true of the cuffs of the jacket, and there are also vents in the shoulder areas of the jacket, close to where an auto-dump would be, to reduce the chance of air getting trapped during an ascent.
These vents are backed by a windproof material, so there is no unfortunate chilling ventilation when the jacket is being used in its own right between dives.

Ease of Use
The idea of wearing an undersuit in two parts is fairly new. It makes climbing into it in the privacy of your car in a municipal car park more convenient, and you are less likely to be accused of making an assignation with a Premier League footballer for a spot of dogging.
The problem arises when the two parts separate while you are under water, leaving
you with a chilled middle. Thats taken care of.
A couple of adjustable crotch-straps stop any tendency for the top to ride up. These straps are removable if need be.
Despite its sleek appearance, I still found the SubXero quite bulky when it came to squeezing my snake-like hips into my drysuit.

The undersuit is, of course, exceedingly warm. Wearing it for a stroll on the beach in June produced so much sweat that I was in need of a shower long before I got my drysuit on.
There was never any hint of getting chilled during the dive. The inner lining is designed to wick away sweat, and it needs to. The SubXero is made of 400g shearling fleece, which provides the highest level of insulation. The hydrophobic nature of the material means that it continues to give some thermal protection even if your drysuit should suffer a massive leak.
The manufacturer claims that independent testers have rated this the warmest undersuit they have ever tried - and I can well believe it.

Weezle Oxygen 2 Piece, £225

Jacket £120, Salopette £100
MATERIAL Microfibre
SIZES 9 sizes, S - XXL
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