THE MOMENT I CLIMBED INTO this undersuit, I was reminded of Christopher Robin in his woolly sleep-suit in the stories by AA Milne, illustrated so ably by Ernest Shepard. The fact is that it made me into one big cuddly giant.
I tell you this only in case you see yourself as a magnificent macho male.
The stretchiness of the material combined with its softness made it fit where it touched. Thankfully, its softness made it comfortable where it touched too, and it touched all of me.
The function of an undersuit is to keep the outer layer, the cold drysuit, away from your skin and provide a volume of thermally insulating air to keep you warm. Because the filling is almost thermally inert, it both blocks convection currents and limits conduction.
I have to say that, reduced to writing in a cold attic in January, thanks to decorators invading the ground floor of my house that includes my office, I felt like keeping it on after trying it for size. It fitted and felt snug.
The suit has elasticated foot-ends that become stirrups, a two-way diagonal zip and a useful pocket for a car key or the like.

Is It Warm When Diving
Feeling snug and warm in one’s attic has no bearing on the performance of a product intended to be used at the pressure of depth, but the Bare SBS Mid Layer is constructed from Polartech Powerstretch fleece, which is designed to maintain these insulating values at changing pressures.
The four-way-stretch nature of the material and high warmth-to-weight ratio of the material bodes well for a good fit, too, and I’m told that it has “moisture-management technology” or what we would call good wicking properties for sweat. It doesn’t feel clammy.
I’m also told that it includes an anti-microbial treatment that inhibits the growth of odour-causing bacteria, while at the same time it’s safe to stuff it in the washing machine.
Of course, it’s meant to be worn with some sort of base layer, hence “Mid Layer”.
I wore it with my trusty Merino wool Icebreaker underwear.
So is it warm when diving I have no way of making a real comparison but I can tell you that I went diving in Wraysbury Lake in January while wearing it under my O’Three Ri200 suit, and suffered only cold hands and face.
I’d go so far as to say that it felt luxurious, and how often can you say that when diving in an English lake in winter
Another nice aspect is that the wind doesn’t whistle though it when you take off your drysuit after a dive. A not-so-nice aspect is its price.

Fourth Element Halo 3D, £300
Weezle Extreme, £172
O’Three PBB Extreme, £170

PRICE £235
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