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Men's Mountain Backpacking Modular Pants - Trek 100

Sale price: $34.99 Regular price:
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This product runs small

Sale price: $34.99 Regular price:

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Model: 8317947

Product Videos

Product Features

Men's Mountain Backpacking Modular Pants - Trek 100 is designed for regular mountain hikers.

2-in-1 pants: transform into shorts.

A photo of the Men's Mountain Backpacking Modular Pants - Trek 100 in use


Durable micro-ripstop fabric that prevents tearing.

Freedom of movement

Semi-elasticated waist to avoid compression anywhere. Preformed knees.

Quick dry

A synthetic fabric that provides breathability and is quick-drying.


Pants convert into shorts using a zipper around the thigh.


Lightweight synthetic fabric that allows body heat to escape.


Lightweight, compressible fabric. About 13.1 oz in size 36.

Easy to maintain

Machine washable synthetic fabric, requires no ironing.

Easy to maintain

Synthetic fabric which is machine washable, does not require ironing.

Product Lifestyle Image Gallery

Image Gallery

Men's Mountain Backpacking Modular Pants - Trek 100,carbon gray 

Men's Mountain Backpacking Modular Pants - Trek 100,carbon gray 

Men's Mountain Backpacking Modular Pants - Trek 100,carbon gray 

Men's Mountain Backpacking Modular Pants - Trek 100,carbon gray

Product Customer Reviews

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1613 Reviews
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Men's Mountain Backpacking Modular Pants - Trek 100,carbon gray
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Best Trek Pant

Its far better than any other high brands, i have used it for short hiking trek its very comfortable easy to carry and quick dry, go for it✌️ for trek video check on my youtube ch "escaping shades"



Great product. Fits as expected

Great quality and fits perfectly. I had to change it 3 times as I was not aware of my size and due to voice trial rooms were closed. But decathlon exchanges the product without asking a single question

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Terrecking trousers

Sizing small had to return swap size

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Good product.

Price worthy

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Size & Length Matching Issue

As per waist size & heightened the delivered product was too long in length, whereas there should be option for bottom attachment length adjustment. If altered, its looks will get disturbed & also its 2 yrs warranty which will be difficult to claim due to altered its height.

Hello Sachin

Thank you for taking out time to give your valuable review. We have a 90 days replacement/return policy for issues like size mismatch. Please feel free to reach out to your nearest decathlon store for the exchange and return process.


Product Trainer and Passionate Backpacker

Awesome product

Very attractive product

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About product

Good product and very useful

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The detachable torso are really useful while you are involved in some water activities. Material is good enough.

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Perfect Fit

It solve the purpose. Quick dry and comfort fit with lots of useful pockets.

Trekking trousers

Modular and light weight. Comfortable pair of pants!

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Hi Tian Siang

Thank you very much for taking time to send me your reviews on " Men's Mountain Trekking Modular Trousers Trek 100 - Dark Grey!"

I am so glad that you love our Trekking Modular Trousers! The flexibility to allow the user to convert the pant into a short with a zip around the thigh is a clever design for many trekkers. Weighing only 370 g, it's a must have for many trekkers or campers.

Keep your sharing coming!

Continue sporting and stay fit!


Caroline Lee

Front Line Customer Service Adviser & Zumba Diva

Decathlon Joo Koon

Using Since 2018

Purchased in 2018 and still using in 2020...

Very good

Very good

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Just take it

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Size Guide

Size Guide Visual

Additional Product Information


Main fabric

  • 100% Polyamide


  • 100% Polyester cationic

Sizing info

Sports cut that offers good freedom of movement. 33.3" pants inside leg in size 36 (L) 10.2" shorts inside leg in size 36 (L)


2 hand pockets 2 cargo pockets with flap 1 zipped side pocket 1 zipped back pocket

A score for comparing the products' environmental impact

The product's environmental footprint is calculated over its entire lifespan using various indicators. A 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.) Decathlon is committed to displaying the environmental Information of its products. Web: Explanation video:



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Size Guide Visual