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Men's Merino Wool Long-Sleeved Backpacking T-Shirt - MT900

Sale price: $99.99 Regular price:

With high weight (240 g/sqm), a stand-up collar and thumb loops, this t-shirt will keep you warm in the depths of winter.

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Sale price: $99.99 Regular price:

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About this item:

  • Warmth: This thick T-shirt (8.5 oz/m²) with Merino wool is comfortable up to 50°F
  • Weight: 5.1 oz in size M.
  • Odor control: Merino wool naturally prevents unpleasant odors
Model: 8580374

Product Features

Men's Merino Wool Long-Sleeved Backpacking T-Shirt - MT900 | Our team of backpacking enthusiasts designed this t-shirt perfectly suited for cold weather use thanks to its Merino wool composition!

With high weight (240 g/sqm), a stand-up collar and thumb loops, this t-shirt will keep you warm in the depths of winter.

A photo of the Men's Merino Wool Long-Sleeved Backpacking T-Shirt - MT900 in use
A photo of the Men's Merino Wool Long-Sleeved Backpacking T-Shirt - MT900 in use


This thick t-shirt (240 g/sqm) made from Merino wool is comfortable down to 10°


Helped by the inserts with their inner side weaved in channels

Odor control

The component limits perspiration odours. Laboratory test ISO 17299-3


Easy ventilation with its very low zip

Abrasion resistant

Use of a wool yarn protected by a surrounding polyamide yarn


Ultra-fine (18.5 microns) Merino wool. It is soft and pleasant to wear


The t-shirt weighs just 350 g in size L. 240 g/sqm and 260 g/sqm fabrics

Questions & Answers

Product Customer Reviews

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437 Reviews
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Completely content.

Great item, you can go out without an additional jacket. Sleeves are a bit long and you can push them back because they fit snugly.

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I'm quite happy

After the first wash, 3 threads were loose, but since then I've washed it again 10-15 times at 20 degrees and the material holds up. It's really awesome how thin it is, well ventilated and I didn't get sunburned on a motorcycle tour in South Asia. So I'm very satisfied. Please offer a color other than blue... e.g. sand/cream color.

Worse than synthetic.

Worse than a synthetic bottom layer. Worse, because wool can absorb even more moisture than cotton. It's one thing that (supposedly) wool is pleasant to wear even when wet... but the task of the bottom layer would be to drain away sweat, and wool fabric is not suitable for this. It didn't work for me, I took it back. In addition, wool, even mixed fiber, cannot be as close-fitting as 100% man-made, synthetic. That is, it stops - so it is even more unsuitable for draining sweat. I tried 5 wool (mixed wool fiber) underwear and "long-sleeved hiking shirts" from the Decathlon range, and none of them were close-fitting. As a base layer, it's not close enough to the body and is probably too thick. And if you were to wear synthetic underwear, the sleeve might be too tight. It can be good to be in this at the accommodation or to sleep in this sleeping bag, especially in cold weather. I definitely do not recommend wearing it as an under layer during a tour.

Almost too hot!

Almost too warm for an underlayer, ultimately basic merino undershirts costing 50 euros are better suited. In any case this one is at least 10 euros too expensive.

Merino top

It's hot

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Merino wool shirt

Very good product but very expensive.

pleasant to wear...

pleasant to wear leaves the skin very dry

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Super hot

Super hot

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super hot

extra for skiing and winter hiking

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Super mid layer

Pleasant merino wool, for me the main shortcoming lies in the length of the body part. The length of the sleeve is fine, however, even at size 2XL, the sweatshirt is not long enough. I am 194 cm tall



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very good product.

very good product.

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Additional Product Information


Main fabric: 89.0% Wool, 11.0% Polyamide ; Yoke: 9.0% Polyamide, 63.0% Wool, 4.0% Elastane, 24.0% Acrylic

Information about the materials used

This t-shirt has a hybrid design to enable the optimal balance between warmth and breathability.We use 2 fabrics:- the main fabric made from 89% merino and 11% polyamide (for durability). 240 g/sqm- the fabric used as inserts, particularly the back and inside of the forearms is made from 63% merino, 24% acrylic (facilitates drying), 9% polyamide (for durability) and 4% elastane. 260 gr/sqm

Tip before use

For a softer feel, wash your t-shirt before first use.

How to wash your merino wool t-shirt?

We recommend that you machine wash your MT900 MERINO wool T-shirt at 30°C on a normal cycle, preferably with liquid detergent. Dry flat and NEVER tumble dry unless you want it to shrink by one or two sizes!



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

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    Minimal retail footprint

    lowers overhead and indirect costs


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