Product Colors and Sizes

  • Black Friday product
  • New Deal product
  • Cyber Monday product
  • Clearance product
  • Deal product
  • Best Seller product
  • Ecodesign product
  • New product
  • Staff Pick product
  • In The News product
  • Innovation product
  • product

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).

Color: Select a color
Size: Select a size
Size Guide
Sale price: $34.99 Regular price:

Free shipping over $35

Free returns

Free pickup

San Francisco, 735 Market St. Options

Select an available color and size to see options.

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

Skip to reviews
996 Reviews
Write a Review 

Ski 580 I-Soft, Thermal Underwear Base Layer Top, Men's,black
Filtered by reviews Loading reviews…

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.

icon-circle-checkmark verified purchase

Great product keeps you warm

icon-circle-checkmark verified purchase
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.

icon-circle-checkmark verified purchase

Hi Corbin,

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

base layer

great value for money

icon-circle-checkmark verified purchase
Value for money

Keeps shape after wash on cold cycle

icon-circle-checkmark verified purchase
Ski season nearly here

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

icon-circle-checkmark verified purchase

Brought this last month, an S size is perfect for an M body to make you look good in the gym!

Worst Product

I never ever expected that worst quality product in that high price... I am using this product for last 1 month on and off but this product is ok in normal winter but in extreme cold weather I didn't found this able to protect at all Better to buy the fleece one inner from local shop that's much better then this


icon-circle-checkmark verified purchase

I invested my money on a waste product, which couldn't give me enough warmth, when I Landed in Vancouver Canada. Decathlon items are a quality and prices are very high.I felt I'm cheated

icon-circle-checkmark verified purchase

Hi Balasubrahmanyam

Thank you for your review and we are sorry that the product did not match up to your expectation.

Men's Seamless Ski Base Layer Top - BL 580 I-Soft - Black/Blue-

As mentioned In the name of the product, this product is designed to be used as a base layer while performing the sport of skiing which helps you to retain warmth and also helps you from getting cold by easily removing the sweat on your body.

The name I soft stands for the Isothermal nature of the product to give warmth and cold according to the condition and the requirement.

Hope these details help you. If required with any other help please write back to me.

Product Not meant for Trekking

This is being sold as a trekking base layer meant to stand up to minus 10 degree. Which is absolutely wrong. The material is flimsy and only looks fancy. Decatalon has much better trekking gear than this. Please do not buy this for any cold /high altitude trekking. For Fancy Dress Competition yes.

icon-circle-checkmark verified purchase

Hello Chandan,

Thank you for the review.

I have responded to your review on the same Base Layers' trousers. I hope that is relevant.

We hope to serve you better in the future.


Jaswinder Singh Maan.

Merchandiser, Decathlon Sports India.



icon-circle-checkmark verified purchase
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.

icon-circle-checkmark verified purchase
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

Skip to reviews

Size Guide

Size Guide Visual

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