Check out Icebreaker bodyfit 200/260 marino base layers. These are fantastic, wicking and stink proof!! I use them for skiing in January. My step son works as a farrier in Norway and swears by them (the 260 knit).
Listen to this man!
Merino wool is your friend out there. I have the 260 and swear by it.
Your Brizzol based too aint ya? so get down Ellis Brigham just up from the zoo and get their advice.
Oh and Iceland in March wont be ANYTHING like North Sweden in January
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so I wouldn't go overboard!
Also to note is that if this is an organised trip, they WILL NOT let you freeze to death out there, more than likely supply you with a "thermal onsie" type thing if it's really brass monkey weather (which I don't think it will be at that time of year)
I was given this in the IceHotel in Sweden.
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(it was -32°C on the day I went out on the snowmobile!)
and very similar when up on the Glacier in Iceland while on the Snowmobile there.
and if you've never had your camera out in proper cold weather, expect it to die after about 5 shots!!
You'll be needing a spare battery selotaped to each *** to keep them warm!
Layering is the key, not just one big puffy jacket that looks like you're wearing a quilt!
Spend the proper money on your base layers and get ones that fit well, (I do so love my Arc'teryx gear
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) try everything on as you wish to wear it too, you'll be surprised how you have to accommodate things like three different layers all having neck zips for eg, You have to get the kit to go together.
What kit would I suggest..
Gore-tex insulated boots and merino wool socks
Merino Icebreaker 260 full length leggins
Ski pants or insulated trousers (NorthFace ski or Craghoppers insulated trousers)
Merino Icebreaker crew neck
thin well fitting fleece --- > I absolutely adore this
http://www.arcteryx.com/Product.aspx?EN/Mens/Mid_Layer-Sweaters/Delta-AR-Zip# Was wearing it yesterday at the Rolling Road Mini meet.
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Synthetic insulated mid layer with insulated hood.
I really don't think you'll need the full parka insulated down jacket.
The above list is also more useful back at home when it's just "a bit nippy out" compared to the full on jacket, ten mins after putting one of them on in the UK and you'll be sweating your balls off
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