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Mountain Bike Hydration Backpack ST 900 12L 2L Water - Black

Sale price: $99.99 Regular price:

The 12 litre capacity is well-distributed for bringing what you need. Enjoy the mesh at the back and various adjustments.

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Sale price: $99.99 Regular price:

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San Francisco, 735 Market St. Options

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About this item:

  • Capacity: 6 L bag with a 2 L bladder for hydration
  • Multiple compartments: Many compartments for tool and item storage
  • Stability: Adjustable straps
  • Carrying comfort: Mesh straps and foam padding for excellent comfort
  • Use: For hiking, camping, and other outdoor activities
Model: 8300158

Product Features

Mountain Bike Hydration Backpack ST 900 12L 2L Water - Black | This hydration backpack is designed to keep you easily hydrated when mountain bike touring for less than 4 hours.

The 12 litre capacity is well-distributed for bringing what you need. Enjoy the mesh at the back and various adjustments.

A photo of the Mountain Bike Hydration Backpack ST 900 12L 2L Water - Black in use
A photo of the Mountain Bike Hydration Backpack ST 900 12L 2L Water - Black in use


A usable volume of 12L and a 2L water bladder: drinking for up to 4 hours.

Multiple compartments

1 large compartment, 1 tool pocket, 2 side pockets, 1 helmet gusset, etc.


Adjusts with the shoulder straps, the waist strap, and the chest strap.

Carrying comfort

There are 3D mesh pads at the back and hips for ventilation.


The bag comes with a built-in protective rain and mud cover.


VIOO CLIP light attachment point on the back

Questions & Answers

Product Customer Reviews

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Good surprise

I compared this bag with the Camelbak equivalent, it is better in every way, at least for those like me who are looking for a large capacity.

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Very good backpack

A decent backpack, good quality. I haven't detected any flaws, I have no problems with it. I use it for MTB trips, for example 80 km. I have no objections.

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comfortable backpack…

comfortable, practical backpack with good support in the back, perfect for mountain biking

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great backpack


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Very practical and good…

Very practical and good support

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Good Qusli

Value for money, too expensive!

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It’s easy to use it as a cycling backpack by removing the water bag, so why not create a cycling backpack?

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Good support and good…

Good support and good storage capacity

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Excellent product, for walking, cycling, shopping...

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I come from a Camelbak that has lasted me more than 10 years. For now this has been a good replacement. Very comfortable, well made, the internal organization with all the divisions is much better, it fits perfectly and looks very good. Let's see if it lasts as long as the Camelbak.

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very good option that competes against big brands

The backpack is a great purchase for various activities. ski, bike and even for the motorcycle. Compete against big brands at less than half the price. It fits everything you need for a day of sports (some clothes, raincoats, food, keys, wallet, etc.) very narrow, does not bulk up and does not shift weight when you move on the motorcycle or skiing. The grip would be 10 if you used the kriega type rotation system. but it is equally comfortable and holds well.

Very practical for…

Very practical for mountain biking or hiking

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super practical, good value…

super practical, good value for money

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hydration backpack

Sturdy and durable, easy to carry but a bit small

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Additional Product Information


Bag: 50.0% Polyester, 50.0% Polyamide ; Water pouch: 100.0% Thermoplastic Polyurethane

Maintenance tips:

For hygiene reasons, we recommend cleaning your water bladder after each use. To help you clean out the tube, you can order a special brush using product ref. 5935596. This kit comes with a hanger to make it easier to dry out the inside of the bladder.Tip: If you don't want your drink to taste like plastic, wash the bladder, dry it well, and place it in your freezer. Take it out a few hours before your ride. This will stop any flavour transfer.

Bring with you...

This hydration pack comes with a 2 L water bladder. But also remember to bring:- your food (granola bars, energy gels, etc.)- your multi-function adjustment tool (ref: 8386669)- a puncture repair kit (inner tube, tyre lever, hand pump, puncture repair spray, CO² cartridge, etc.)- your chain rivet extractor and a quick link - a piece of identification, blood type card- a means of payment and a telephone- a 1st aid kit- etc...

A large water bladder

With its 2-litre capacity, your water bladder will last you around 3 hours of riding. Its wide opening makes it quick to fill up. When closing it, make sure the slider clips into place to ensure it won't leak.

Great water flow

Before you set off, remember to remove the air to improve water flow. Just turn the hydration bladder upside down once filled, direct the air bubbles towards the tube opening and suck them out. The bite valve is lockable (rotates 180°) to prevent leaks when not in use. It won't drip, even when in the open position. To get a good flow when drinking, pinch the valve with your mouth and suck.

Care tips

To make your bag last longer, we recommend waterproofing it before you first use it. Even though the fabric is already water-repellent, extra waterproofing will stop mud getting caked onto it. Before each ride, remember to wash and dry your water bladder with the help of the cleaning kit (product ref. 5935596).If you don't want to get a plasticky taste, put your dry water bladder in your freezer. This will stop any flavour transfer.

Extending the product's lifespan

Remember to take a look at our water bladders support page to help your product last longer.

Product testing

At Decathlon, all of our products are tested by a panel of users in the conditions for which the products were designed. These tests are led and monitored by our design team. All of these tests allow our product managers, engineers and the whole mountain biking team to develop, create and design technical products that guarantee customer satisfaction.

Storage instructions

Once clean and dry, keep your backpack and water bladder in a dry place and away from direct sources of heat. Clean by hand in soapy water.



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