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Forclaz Trek 900 Long Sleeve Merino Wool Backpacking T-Shirt

Sale price: $70.00 Regular price: $94.99

With a high density (8.5 oz/m²), a high neck, and thumb holes, this T-shirt will keep you warm in the winter cold.

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Sale price: $70.00 Regular price: $94.99

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San Francisco, 735 Market St. Options

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Model: 8580374

Product Videos

Product Features

Forclaz Trek 900 Long Sleeve Merino Wool Backpacking T-Shirt | Our team of backpacking enthusiasts developed this Merino wool T-shirt that is specifically designed for cold weather!

With a high density (8.5 oz/m²), a high neck, and thumb holes, this T-shirt will keep you warm in the winter cold.

A photo of the Forclaz Trek 900 Long Sleeve Merino Wool Backpacking T-Shirt in use


This thick T-shirt (8.5 oz/m²) with Merino wool is comfortable up to 50°F


Improved thanks to inserts with an inside face knitted in canals

Odor control

Merino wool naturally prevents unpleasant odors


Easy to ventilate with its very low zipper

Abrasion resistant

Use of a wool yarn protected by a surrounding polyamide yarn


The T-shirt weighs just 5.1 oz in size M. 8.5 oz/m² and 9.2 oz/m²


Ultra-fine (18.5 microns) and very soft Merino wool. Does not itch

Product Customer Reviews

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285 Reviews
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Forclaz Trek 900 Long Sleeve Merino Wool Backpacking T-Shirt,butterscotch
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Great buy

Awesome all around warm shirt to wear anywhere or can also serve as a layering piece.

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Great buy!

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Merino win!

Fabulous value and quality!!! Great function, fashion & price!!!!

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Hello Joe! 


I know right, merino wool is the best, the fabric, the feel of it always stands out. :)

Thank you for taking the time to write to us about your product experience.

Wishing you a fantastic day :)


Decathlon Brampton Team

Great warm top

Good percentage of merino wool in this top. It's heavier than the other merino tops. Nice style, with the contrast yellow zip pills, and it has a small slanted chest pocket. Probably around 20% cheaper than other big name branded merino tops. Very warm and light, great mid-layer.

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Trekking merino long sleeve shirt

Fab value. Really good fit and so versatile. The long front zip is perfect to help with cooling off. It also washes great on a standard (not wool cycle!) 40° wash without shrinking - I found that out by accident. I’ve bought a couple of these now as I really find them super comfortable.

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light jersey more than t-shirt

have been using this more as a mid-layer than a t-shirt. feels like good quality.

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Useful piece of clothing. Can be used alone or under a warm layer to increase cold protection. Odor control is good.

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Awesome product by Decathlon


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I used this merino jersey during Annapurna Base Camp trek in Nepal last 2 weeks. It is an awesome product- comfortable, warm, lightweight and very breathable. No odor and dries quickly, despite having sweated profusely in it during the hard trek, An excellent product.

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Product is good

Ok ok product. Not something worth the price

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Добър продукт

Блузата е добра, дишаща, топли, не спарва. Все пак отпред е малко странна с този шев по средата.

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Благодарим Ви, за отделеното време да споделите обратната си връзка за нашия продукт!

Като спортна компания, която се стреми да направи спорта достъпен за всеки, нашата цел е винаги да предоставяме качествени и функционални продукти.

Спортни поздрави,

Екипът на Декатлон България

Ideální na cestování

Ideální tričko na cestování.

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Merino rolák

Poměr cena/kvalita naprosto super.

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překvapivé, srovnatelné s renomovanými značkami

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Size Guide

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Additional Product Information


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

Information on 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). 8.5 oz/m²- the fabric used as inserts, particularly the back and inside of the forearms, made from 63% Merino, 24% acrylic (facilitates drying), 9% polyamide (for durability), and 4% spandex. 9.2 oz/m²

Odor control

Wool from Merino sheep naturally controls the spread of bacteria that cause bad odors. This Merino wool T-shirt can therefore be wornseveral days in a row and means you can take less clothes when backpacking making for a lighter backpack!

Tip before use

For a softer feel, wash your T-shirt before 1st use.

How to wash your merino wool t-shirt

We recommend that you machine wash your Trek 900 Merino 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 1 or 2 sizes!For more information:



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Size Guide Visual