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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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San Francisco, 735 Market St. Options

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

Too loose fitting size , worst product

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Thank you for taking the time to give your valuable review. We are sorry that you were not satisfied with the product. Please visit your nearest Decathlon store for an exchange or refund.


Product Trainer and Passionate Backpacker

Light weight,very nice

Very good product

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Come with a lot of pocket. Comfortable. Able to convert long pants to berm.

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Hi Kum Fatt,

Thank you for taking the time to review our products. We are pleased to hear that this item meets your expectations!

We look forward to more of your reviews and sharing! Plus, the new Decathlon app has been launched and you can now purchase all your favourite sports goods with just a few clicks on your smartphone! Yes, it's now available both in the App store and Google Play Store! Download now and happy shopping!

Thank you for your support and stay safe! :)

Sport on safely!


CSM Digital Leader

Product Feedback

Good product...little longer from bottom but product quality and color is superb..!!

Great product

I purchased this for Tungnath trek and it served the purpose very well. Just make sure to choose the correct size, I used to wear 32 waist for Levis denim but 32-33 waist size trek pain was fit for me.

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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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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