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Forclaz Trek 500, Merino Wool Tights Backpacking Undergarment, Men's

Sale price: $59.99 Regular price:

Looking for a comfortable anti-odor base layer? These long-lasting reinforced Merino wool tights are ideal.

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Sale price: $59.99 Regular price:

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Model: 8501932

Product Features

Forclaz Trek 500, Merino Wool Tights Backpacking Undergarment, Men's | Our team of backpacking enthusiasts developed these Merino tights so you can trek for longer without worrying about bad odors

Looking for a comfortable anti-odor base layer? These long-lasting reinforced Merino wool tights are ideal.

A photo of the Forclaz Trek 500, Merino Wool Tights Backpacking Undergarment, Men's in use

Odor control

The Merino wool (86%) naturally helps prevent unpleasant odors.


Tights made of merino wool to provide an extra warm base layer

Abrasion resistant

Use of wool fiber surrounded by polyamide yarn for protection.

Moisture wicking

The high absorbency of wool helps keep the body dry


Merino wool is breathable and helps maintain the right body temperature.

Freedom of movement

We have added 4% spandex for superior elasticity and support.


Tights weigh just 6.7 oz in size M. Fabric 6.7 oz/m².


Ultra-fine (18.5 microns) Merino wool. It is very soft and doesn't itch

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Forclaz Trek 500, Merino Wool Tights Backpacking Undergarment, Men's,black 

Forclaz Trek 500, Merino Wool Tights Backpacking Undergarment, Men's,black 

Forclaz Trek 500, Merino Wool Tights Backpacking Undergarment, Men's,black

Product Customer Reviews

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Forclaz Trek 500, Merino Wool Tights Backpacking Undergarment, Men's,black
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Warm, comfortable, and being wool doesn’t hold oder.

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Excellent,and effective

Great product, used these sailing under walking trousers and waterproof layer, went fully into the water and was as warm as those in wetsuits. retains heat well when wet and comfortable and well made, a pleasure to use. One of my best purchases of 2020

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Very comfortable

These base layer tights are great. Good fit and comfortable as well as being lightweight and warm. Would definitely buy again. Great price too !

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Quality and value

Much better quality than similar weight base layers from other brands and, these are at a great price

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Great purchase

These are excellent - better quality and warmer than some much more expensive ones that I've purchased elsewhere. I'm really pleased with them.

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Used for skiing in Switzerland it was really amazing kept me warm and worth every penny

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Size Xl

Nice and warm

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Overall a satisfactory pick

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Not Satisfied

As it is costly but not worthy in warm.

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Hello Sudhir

Thank you for taking the time to give your valuable review. We are sorry that you were not satisfied with the product. MT500 is a merino wool base layer designed for trekkers to be worn for several days, The main promise of the product is that the material is naturally anti-bacterial and reduces odour. Hence, It only needs one merino base layer for a 5-7 day trek where you would need 3 polyester base layers.


Product Trainer and Passionate Backpacker

Lower Base layer


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Will buy again

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Not very affective in winter

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A very good product

This product is as my requirement. I love it.

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Excellent inner wear

Excellent inner warm wear

Not very warm

I bought these for a 10 day trip to Ladakh in October. The decathlon sales person recommended these over the basic Wedge tights and said that these would be warmer as they are made of Merino. Honestly, I didn't feel much warmth with these under the Trek 900 pants. The Wedge base layer is much warmer in my opinion. Also, the elastic band around the waist is horrible with a size S running between 87-92 cms (about 34 to 36 inches). The tights keep running down if not worn with another layer on top to secure them. I don't what size slimmer guys like me are going to get.

Hello Mr. AR
Thank you for taking out time to give your valuable feedback . We are extremely sorry for the bad experience you had. 
We generally recommend Merino wool for long trips like yours because their major benefit is that they are anti bacterial because of the type of wool you can use them for multiple days ,even upto seven days while Backpacking  or Trekking and the product won't develop  any bad odour and also they are warm.
However we really appreciate you writing us about the elastic fault and expressing your dissatisfiction, Please reach out to your nearest Decathlon store and get your product exchanged or refunded.
I hope the information was helpful, kindly write back to me in case of any further queries.  

Product Trainer and Passionate Backpacker
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Size Guide

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Additional Product Information


Main fabric

  • 86% Wool
  • 10% Polyamide
  • 4% Spandex


  • 98% Wool
  • 2% Polyamide

Sizing and fit

These tights have a close fit to help the transfer of moisture to the outside of the fabric. 4% spandex added for comfort and freedom of movement.

What is our commitment to animal welfare?

We only use wool from Merino sheep bred on farms in South Africa that do not practice mulesing. We decided to build a partnership with a group of breeders (Konsortium Merino) to guarantee respect for animal welfare and the environment. We have full traceability, which allows us to guarantee the origin of the wool.

How have we reinforced the durability of these merino wool tights?

Use of a BETA-SPUN yarn structure in which the polyamide threads coat the Merino wool fibers and protect them from rubbing and cuts without affecting their properties.

Odor control

Wool from Merino sheep naturally controls the spread of bacteria that cause bad odors. These Merino wool tights can therefore be worn several 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 tights before 1st use.

How do i wash my merino wool tights?

We recommend that you machine wash your Merino wool tights at 86°F 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!



Product testing

In November 2018, 8 backpackers (4 men and 4 women) and part of the Forclaz design team, tested these tights for 4 days in the southern French Alps (Lus La Croix Haute). On the agenda, wind, rain, a bit of snow, a bivouac... and a lot of fun! We were then able to make the final modifications and validate it for use for backpacking.

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.

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Size Guide Visual