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Ski 580 I-Soft, Thermal Underwear Base Layer Top, Men's

Sale price: $34.99 Regular price:

Enjoy the unprecedented comfort of this incredibly soft 2nd skin thanks to its I-Soft technology (brushed fabric).

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Sale price: $34.99 Regular price:

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Model: 8548379

Product Features

A photo of the Ski 580 I-Soft, Thermal Underwear Base Layer Top, Men's in use

Ski 580 I-Soft, Thermal Underwear Base Layer Top, Men's | Developed for skiers who ski at a moderate intensity (high perspiration) in cold weather, seeking a comfortable and extremely soft 2nd skin.

Enjoy the unprecedented comfort of this incredibly soft 2nd skin thanks to its I-Soft technology (brushed fabric).

Moisture wicking

Good: intelligent bodymapping for effective transfer and fast drying.


Average: bodymapping integrated into brushed component for a feeling of warmth

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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838 Reviews
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Ski 580 I-Soft, Thermal Underwear Base Layer Top, Men's,black
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Very happy with this purchase. However, other more affordable options are available that are warmer. However this product breathes slightly better, the competitors product makes you sweat more.

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Great product keeps you warm

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Pretty good

I was afraid that the base layer would not be very comfortable because it is not made of wool but I was very pleasantly surprised.

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Hi Corbin,

Thanks for sharing! We are happy to hear that you are satisfied with this item!

Value for money

Keeps shape after wash on cold cycle

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Ski season nearly here

Another excellent fit. Great quality as usual and can’t wait for the new season.

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Vary Bad Product

Poor quality product ....

Hi Sajad,

Thank you very much for highlighting the issue faced with the product and we are sorry that you had to go through a not-so-great experience. Please write back to me and explain the main concern faced in the issue so I can help you with it better. I believe with the information provided by you, I will be able to provide a better resolution.


Good product.

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It is not warm.

I purchased it because i thought it will be warm but it is very normal. So if you purchasing it with the thought that it will give you heat,dont buy it.

Hello Javaid

Thank you for taking the time to give your valuable review. We are sorry that you were not satisfied with the product. This base layer is designed for Ski and hence along with warmth moisture management and reducing chafing is also its major technicity as you are very active while skiing. However, we understand that if you bought these for normal purposes when you are static and not in too much action the level of warmth would not be great.

We apologise for not being able to guide you during the time of purchase, Please feel free to return the product at your nearest Decathlon store or via your Decathlon mobile app.


Product Trainer and Passionate Backpacker

Amazing Fit

Worth Buying

Superb T-shirt

Awesome T-shirt but r little high

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Very good quality and stretching made for gym and sports lover

Look good but poor quality

Fabric quality is very bad , you can see lint ball everywhere after using few days.

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Gem of product, unlike other brand normal thermals made of cotton or polyester, it is made of polyamide so NO RASHES and ITCHING; HEAT MAPPED so not SWEAT LOGGING, ODOR or WET FEELING -balance of warmth and perspiration wicking, so suited for ACTIVE SPORTS- DRIES FASTER. Unique feature- We can wear WHILE TREKKING (can't do this, with other thermals-which will make us feel overheated, suffocated & ultimately our sweat itself will make us feel chill) and of course, in night while sleeping. Add on feature, with good body hugging elastane, they act as COMPRESSION T-shirt, which means FASTER MUSCLE RECOVERY after a tiring trek/hike, ask any sportsmen compression tees advantage. Yes, bit of wobbling, but I researched, design wise doesn't affect core functionality, infact normal for a thermal or sweater (in any case this is base layer we sleep with this on, and we wear fleece/ jacket etc over it). This unique weaving and wobbling helps it to trap more air and thus better insulation of body heat and prevent outer cold getting in. Difficult to balance warmth and sweat absorption with such a thin fabric- Technology put in use:) LOVED IT. Worn this during Buranghati and Sandakphu trek- Must buy and try yourself, HIGHLY RECOMMENDED. (Guess what my wife who also wore the female version of this product agreed on this- that doesn't happen, often :):)

Good Quality and value for money

Good Quality and value for money

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Excellent fit, comfort n sweat absorbent

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Size Guide

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Additional Product Information


Main fabric

  • 97% Polyamide
  • 3% Spandex

What is the fit of the i-soft base layer?

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

What are the benefits of polyamide?

Polyamide has the highest strength of all textile raw materials (even when wet) and is very stretchy. This breathable fiber manages moisture very well and provides good temperature regulation. These specially textured super-soft yarns give fabrics a silky, natural feel. Ideal for tight, seamless clothing.

Technical structure of the product

Thanks to its intelligent bodymapping and brushed polyamide fiber created from I-Soft technology, this 2nd skin will ensure you feel a warmth that is distributed evenly over the whole body.

What is i-soft technology?

I-Soft technology enhances the fabric's performance, providing a variety of benefits: softness, warmth, and next-to-skin comfort. It also enhances garment performance, providing better heat regulation, humidity absorption, and thermal insulation. To achieve this softness, the base layer is brushed.

What is i-band technology?

I-Band technology is an innovative design used around the waist of the I-Soft top and bottom base layers. It helps keep the garment in place so that it doesn't ride up or fall down when skiing.

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