Turn Your Hydro Flask or Klean Kanteen Into a Filter Bottle with the AquaGear Filter Straw Cap

Aquagear Filter Attachment Turns Hydro Flask or Klean Kanteen into Filter BottleWe’ve never made a secret of our appreciation for Hydro Flask and Klean Kanteen: we’ve looked at Hydro Flasks, reviewed Klean Kanteens, even pitted them against each other. We named Hydro Flask 2015’s best bottle and gave it an honorable mention in 2016 when Klean Kanteen took the crown.

The filtered water bottle has been another commonly reouccuring theme here on the blog, from our filtered water bottle buyer’s guide to our look at bottles with integrated filters such as the LIFESAVER Bottle or the LifeStraw Go. Yet whenever we come across a filtered bottle – as nice as the bottle might be – we are always a little hung up on the fact that it is not our bottle. It is always a bottle forced on us by the manufacturer, a price we must pay in order to make use of their filter. Fair enough, but now the AquaGear Filter is looking to shake things up.


Filter Water With Your Choice of Bottle and the AquaGear

Aquagear Water Filter Bottle Attachment in Klean Kanteen

The AquaGear provides a filter which is designed to filter water which is otherwise already potable. Advertised as removing 99.99% of contaminants commonly found in tap water, the filter should not be used outdoors or in survival situations, but rather to make your otherwise clean or slightly questionable water healthier. It removes things such as pharmaceutical and agricultural pollutants, heavy metals, chemicals like lead, fluoride, chlorine, mercury, and more. A complete listing of compounds removed, along with a variety of testing certificates from independant laboratores, can be found on the AquaGear website.

Using the filter is pretty simple. It is inserted into a comppatibly sized Klean Kanteen or Hydro Flask (more on that below.) The filter is equipped with a straw and relies on suction to move the water up through the filter. The filter itself consists of activated coconut carbon which traps contaminants from the water as it moves through the filter. Further filtration is provided by a technology called CRM Ion Exchange Medias which helps to remove heavy metals and traces of pharmaceuticals.

But Will It Fit My Water Bottle?

Aquagear Hydro Flask and Klean Kanteen Compatibility Chart
Aquagear Compatibility Chart. (View Full Size on Amazon)
As much as we wish it were possible to have a filter which can be affixed to literally any bottle, the day is not quite here yet. Fortunately, the AquaGear is a step in the right direction and there are a few different options for what bottle you can use. Included models are: Klean Kanteen Classic 40 Ounce, Klean Kanteen Classic Insulated 27 Ounce, Klean Kanteen Classic insulated 32 Ounce, and the Klean Kanteen Reflect 27 Ounce.

For Hydro Flask owners, things are a bit more limited. The AquaGear, as it stands, only works with the 21-Ounce Hydro Flask.

We haven’t done much experimentation yet, but there are quite a few bottles we’ve seen with very similar threads to these models. So, while it is not advertised as being compatible with other types of bottles, we suspect there are probably a few others out there which would work. You can view a graphic of compatible bottles on the AquaGear Amazon listing.

Everyday Filtration


It’s not fair to compare the AquaGear to something like the LifeStraw, despite the many similarities in their design. This is because the AquaGear filter is designed as an everyday filtration solution for people living in areas with tap water, not an outdoor survival tool designed to make otherwise dangerous water potable. As much as we would like to see a LifeStraw-esque attachment for our Hydro Flasks and Klean Kanteens, this doesn’t diminish how useful the AquaGear is.

If you’re concerned about things such as lead, fluoride, chlorine, industrial or agricultural pollutants, or any of the other contaminants which are found with shocking regularity in tap water across the globe, something like the AquaGear provides a brilliant, portable, and simple solution to tackling the problem and doing what you can to always ensure you are drinking the cleanest water available.

We hope you are already in the habit of filling up your water bottle throughout the day. With the addition of the AquaGear, you’ve now added quality activated coconut carbon filtration with no additional steps.

Learn More About the AquaGear

To learn more about the product, check current prices, read other customer reviews, or even purchase an AquaGear for yourself, be sure to visit the Amazon listing.


Support Thirst Relief International

Thirst Relief International LogoDoing their part to battle the world water crisis, AquaGear has a partnership with the Thirst Relief International project. Thirst Relief works to provide tools, education, and infrastructure in areas which struggle with access to clean water. Donating proceeds from every sale to helping provide Thirst Relief with biosand filters, AquaGear promises to provide six months of clean drinking water to someone in need for each filter they deliver.

Thirst Relief International works to provide biosand filters, drill wells, repair and maintain old wells, equip schools with much needed equipment for clean water, and more. You can learn more about Thirst Relief and how you can help at thirstrelief.org


Makes Potable Water Cleaner & Tastier
Remove Chlorine & Other Chemicals


Only Filters Potable Water
Only Fits Select Hydro Flask & Klean Kanteen Models

  • Editor Rating
  • Rated 4 stars
  • 80%

The AquaGear Filter Straw seamlessly screws into your Hydro Flask or Klean Kanteen lid, equipping your favorite bottle with a capable filter.

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