When you buy the new Berghaus jacket you get more than a foul- weather garment. For a start, there are three brand names: Polartec, the "climate control fabric", used to make the inner jacket; Gore-Tex, the outerwear material, which is designed to be waterproof and breathable; and Berghaus itself, maker of clothing beloved by everyone from Everest climbers to BBC Radio car engineers.

Moscow, at the harsh end of winter, is an excellent testing ground for cold-weather clothing. Usually, I take a heavy, old and devastatingly effective coat, for which I would guess several creatures gave their wool and/or lives. It threatens to take up the entire baggage allowance on its own, so it was a pleasure to pack a garment that weighs only a few pounds.

A temperature of -15C is an instant incentive to unpack it at Moscow airport. The weight increases substantially with the addition of everything you have to stuff into the pockets. Even in post-Communist Russia, you still need to carry a large number of documents when crossing frontiers. And the decline of the rouble means that a room for a week costs a brick- sized wad of local currency. The Berghaus has hidden pockets that the most assiduous crook or customs official might overlook, and no doubt a few I was unable to find.

The design is confirmation of what my mother always says: that the number of layers is more important than thickness. So the construction is as follows: a Polartec cardigan, which zips inside a Gore-Tex outer jacket, which has a intermediate web rather like a string vest (another good thermal bet, according to my mum). Each of these is designed to allow moisture from the body to escape, while the outer layer is both waterproof and water-repellent: rain forms into beads and rolls off.

Rain is not a problem in Moscow in winter. What is a conflict is the desire to be fashionable versus the need for sensible cold-weather clothing. As a badge, Berghaus is almost as sought-after as Levi's. Yet at first I found the new jacket to be chillingly impractical, as I struggled with a complex system of zips. There is no instruction book for securing the inner to the outer garment, and the whole thing against the elements. Less haste, more warmth is the moral.

Another irritation, which is also probably more a product of impatience and ineptitude than poor design, is the tendency of the inner and outer pieces to separate. All points for style are lost when you turn yourself and the jacket inside out in the process of removing it.

But one failing for which clumsiness is not responsible is the wind-cheating ability. The term "wind-chill factor" takes on a whole new meaning in a Russian winter. While my old three-sheep coat simply blocked out the bitter breeze, the new lightweight jacket seems a mite too flimsy.

Where the jacket really scores is in coping with variation in temperature. Russia is a nation of extremes in all things. A normal day involves veering from the very cold to the suffocatingly hot. Most interiors are overheated to a ludicrous extent, yet you remain blissfully unaware of the reverse osmosis of perspiration. My beastly old coat has no such characteristics, but then it cost nowhere near £350. It turns out that the cost of the jacket is about the same as a one-way flight from Moscow to London.

Berghaus Gemini Chimera, £349.95. Stockist inquiries 0191 415 0200.

Simon Calder