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Thermal Underwear Base Layer Top, Kids'

Sale price: $7.99 Regular price:

A warm ski base layer with brushed component, flat seams, and stretch knit for added comfort.

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Sale price: $7.99 Regular price:

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San Francisco, 735 Market St. Options

Select an available color and size to see options.

Model: 8343744

Product Videos

Product Features

A photo of the Thermal Underwear Base Layer Top, Kids' in use

Thermal Underwear Base Layer Top, Kids' | Our team has developed this skiing base layer for kids. It will bring them the necessary warmth for a great day's skiing.

A warm ski base layer with brushed component, flat seams, and stretch knit for added comfort.

Moisture wicking

LOW: component providing moisture wicking and low-level drying.


HIGH: brushed lining for warmth.

Odor control

LOW: the polyester fiber has a low odor-reducing capacity.


Knitted with very soft thread for extra comfort and softness.

Product Customer Reviews

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Thermal Underwear Base Layer Top, Kids'
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Excellent but VERY small

I ordered the top and bottom for my 7 year old daughter. She is a US size extra small to small (6-7), and she’s very small and short for her age, so I ordered the size 8 years. It was entirely too small. I then ordered the 10 years size and it’s a much better fit. Besides the fit, the quality of the item seems great! There were no weird smells or anything either. Great kids Baselayers, but especially for the price, it’s a steal. Can’t recommend enough - just size up at least two sizes.

Comfortable and useful

Very satisfied!

kids base layer top size8

Exellent garment, good fit, was exactly what I was looking for, my grandson will no longer be codl out on the footy field.

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Good quality

Good quality

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This fits my 9 year old kid well. It stretches a little. If your child 9-10 years old and is above average size, you might try the next size up.

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Great product

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Hello Megan,

Thank you for leaving a review about this product.

Always nice to hear that our customers love their new acquisitions 😉

Have a lovely day,

Decathlon Calgary Team

So so..

It's not bad to wear as an inner, but it creates a lot of fluff. It's cheap so just wear it.

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Hello Jieun,

Thank you again for your comment on this item. This material is very sensitive to high heat. In order to avoid fluff, i suggest a delicate wash on the washing machine and avoid the tumble dryer. I hope this can fix the fluff issue.

We remain available if you have other comments on this product.

See you in store !

Nice and warm

Great fit ! Very warm and kept us dry as we snow tubed

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Perfect winter undershirt

Great long sleeve warm shirt for winter. My daughter loves wearing them under a sweatshirt or sweater to keep her warm without the bulk. Washes well and doesn’t shrink or lose its shape. We have bought one for every day of the week!

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Great for trick or treating

Kept my child nice and warm

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Size up just in case

The fit is quite small. Size up if you want it to last.



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Good base layer

It's a good base layer for kids and the price isn't bad either. Kept my daughter warm even in the rain.

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Bought for my grandson to wear when playing football, excellent product

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Really good

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Size Guide

Size Guide Visual

Additional Product Information


Main fabric

  • 100% Polyester cationic, 100% of the thread is dope dyed

What is the fit of the kids bl 100 base layer?

The KIDS BL 100 base layer is cut to provide a REGULAR fit. It's a classic straight cut that fits every body shape.

What are the benefits of polyester?

Polyester is the most-used fiber for base garments because it is relatively inexpensive and offers excellent performance in various respects, and especially because the fibers can be knitted to obtain a very lightweight and durable fabric. It actively absorbs moisture but does not dry particularly well when wet. It is limited in its ability to reduce odors.

How should kids dress to ensure they keep warm on the slopes?

To make sure you stay warm and dry, we recommend using the 3-technical-layer rule: 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 bad weather.

A product-specific environmental rating

The product's environmental footprint is calculated for its entire life 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 created, 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.

Care instructions

Wash before first use. Machine wash at 30°C. Synthetic cycle. Turn inside out. Dry flat in a well ventilated place. Do not tumble dry. Do not dry clean. Do not iron. Do not place on a radiator.

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