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Ski 900, Thermal Underwear Base Layer Top, Men's

Sale price: $30.00 Regular price: $59.99

The perfect balance of warmth and breathability. The dry yarn is concentrated more highly in high-perspiration areas to accelerate the wicking and drying process.

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Sale price: $30.00 Regular price: $59.99

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San Francisco, 735 Market St. Options

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Model: 8551199

Product Features

A photo of the Ski 900, Thermal Underwear Base Layer Top, Men's in use

Ski 900, Thermal Underwear Base Layer Top, Men's | Developed for skiers who practice at high intensity (high perspiration) looking for a high performance 2nd skin in cold weather.

The perfect balance of warmth and breathability. The dry yarn is concentrated more highly in high-perspiration areas to accelerate the wicking and drying process.

Moisture wicking

High: smart bodymapping to improve perspiration wicking & drying using dry yarn.


High: body mapping through intelligent 3D knitting.

Irritation reduction

Seamless technology: fewer seams to reduce irritation.

Irritation reduction

Seamless Technology: limited seams to reduce irritation.

Product Customer Reviews

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459 Reviews
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Ski 900, Thermal Underwear Base Layer Top, Men's,galaxy blue
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Used as base for drysuit diving in PacNW

I was sceptical but was delighted by the warmth it gave. I am a large (6'1" - 200lbs) usually, but due to stock outage I selected an XL. Glad I was forced to make that choice ! It is snug - but comfortable. It sure did the trick. I did wear it under a full polartec undergarmet and it gave me the extra warmth at 90' that I was previously missing.

Nothing special, kinda itchy

Among my many many purchased base layers, I have this. And it’s not very comfy, not recommended

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Hello Steven,

Thank you for the honest feedback for this product. It will help us improve on our products. :)

Seems great but way too small

Love your products but I wish you'd sort your sizing out. I'm a size M in pretty much everything I buy, but I think this was around two sizes two small - I couldn't breathe when I put it on. I'll reorder in another size though as it seems like a really good top.

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Excellent Value for Money

The top looks and feels very nice and fits well. Will have to wait t try it out on the slopes though.

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Thermal top

Golf thermals don’t do the job. This does but doesn’t have fancy logos.

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maximálně vyhovuje a splňuje vše co jsem očekával

není co dodat úolně perfektní

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tepelná pohoda i odvod potu je velmi dobrý. srovnatelný s výrazně dražšími produkty. Komprese je vyhovují. Doporučuji.

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Teplé a komfortní

Plní vše potřebné i při VHT. Délka vyhovuje a dobře kreje záda i při náročnějším pohybu.

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Sehr zufrieden

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Entspricht den Angaben

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paßt und erstaunlich warm

Das Unterhemd paßt hervorragend, ist weich und hält schön warm. Für den Preis empfehlenswert.

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wie eine zweite Haut, wärmt, atmungsaktiv

Ich habe mir das langarmshirt zum Biken zwischen 0 und 5 Grad unter einer dünn isolierten Radjacke geholt. Es wärmt gut, aber nicht extrem, dadas Gewebe auch sehr atmungsaktiv ist. Ich hatte keine Probleme mit Hitzestau oder Ähnlichem. Die Verarbeitung wirkt ziemlich gut, der Stoff ist sehr elastisch. Es erfüllt den von mir gewollten Effekt. Allerdings würde ich empfehlen eine Nr. größer zu bestellen. Ich bin 1,80 und mit 63 Kg sehr schmal. Normal passt mir überall M mancmal sogar S. Hier habe ich M/L bestellt und es passt gerade so. liegt sehr eng an auch am Hals und die Ärmel sind fast ein wenig kurz. Es gibt echt wenig Klamotten in M, die an meinem Körper hautdirekt anliegen :-).

Super Unterwäches!

Nutze es mehrfach die Woche, hält sehr warm erlaubt aber trotzdem das schwitzen. Sehr gelungen!

Guter Kauf

Trage ich beim Biken unter der Jacke. Super Tragekomfort, hält warm und ist atmungsaktiv.

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Hält super warm und macht jede Bewegung mit.

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Size Guide

Size Guide Visual

Additional Product Information


Main fabric

  • 3% Spandex
  • 17% Polypropylene
  • 80% Polyamide

What type of fit is the 900 base layer?

The 900 base layer comes in a slim fit. It is a 2nd skin with a slim fit that reduces friction.

What are the advantages of polyamide and dry yarn fiber?

Polyamide has the highest strength of all textile raw materials (even when wet) and is very stretchy. It's a breathable fiber that manages moisture very well and provides good temperature regulation.. Blended with polypropylene or dry yarn, this hydrophobic yarn promotes extremely good perspiration wicking.

Technical structure of the product

Thanks to the intelligent 3D knitting, deep insulation compartments are formed. These are insulating chambers that trap warm air coming from your body to create a buffer against the cold.

How to dress to stay warm on the slopes

You just need 3 technical layers to keep warm on the ski slopes: - Layer 1 or a 2nd skin, to stay dry. - Layer 2 or an insulating layer, to keep the heat in. - Layer 3 or a protective layer to protect against the elements.

Determining the environmental impact of our products

The environmental impact of the product is calculated over its entire lifecycle and using various indicators. An overall score from A to E is given to help you easily identify the most eco-friendly products by comparing products of the same type (T-shirts, pants, backpacks, etc.)



Product testing

All Wedze products are conceived, designed, and developed in the Mont Blanc Valley. They are then tested under the same conditions as you would experience in real-life use (snow, cold, powder snow, etc.). The design teams ensure that the program for which the product has been designed and developed matches perfectly with its use in the field.

Storage instructions

Dry thoroughly before storing.

Superior quality. Unbeatable prices.

For 40 years, Decathlon has delivered the best value in the retail sports industry by offering high-quality, sustainable and cost-effective products.

Decathlon makes the difference
  1. product-research

    Research and development

    delivers high-quality cost-effective products

  2. State-of-the-art production processes

    minimize manufacturing costs

  3. Optimized supply chain

    reduces retail prices

  4. laptop-checkout

    Minimal retail footprint

    lowers overhead and indirect costs


Size Guide Visual