ÖKO Purification Straw & Duo Replacement

The official DUO replacement filter straw that works standalone or in-bottle.

Electro-Adsorption Filtration:

  • Reduces and retains 200+ contaminants as water passes through, using membrane technology derived from NASA Spinoff research. Use it standalone in a glass, cup, or straight from the tap, or insert it into your OKOH2O DUO bottle for built-in filtration — independently tested by NSF-accredited laboratories.

Built For Life On The Move:

  • Fast flow rate of up to 1 liter per minute means no long wait for a drink. Rated for 756 liters, roughly a year of daily use, ideal for restaurants, hotels, travel, and camping. Removes and reinserts in seconds, no tools required.

Use with water between 1°C and 50°C. Replace every 12 months.

Regular price
$0.00 USD
Unit price
per

Pay in 4 interest-free installments of $133.12 with

Product Specifications

Dimensions & Weight

  • ÖKO 650ml: 22 oz | 9" × 3" × 3" | 145g (5.1 oz)
  • ÖKO 1000ml: 34 oz | 10" × 3.5" × 3.5" | 160g (5.6 oz)

Materials

  • BPA-free polypropylene
  • Tritan® Cap
  • Food-grade silicone
  • Food-grade TPE and ABS plastic

Filtration Technology

  • Active Technology: Electroadsorption
  • Testing Standards: Tested by multiple laboratories using NSF Standards 42/53 and EPA protocols and standards.

What It Filters

  • 99.99% of viruses
  • 99.999% of bacteria
  • 99.9% of protozoan cysts
  • PFAS
  • Microplastics
  • Metabolites
  • Fluorides
  • And more

Filter Cartridge

  • Lifespan: Up to 100 gallons, variable based on quality of water.
  • Replacement Indicator: Set reminder wheel for the desired replacement month. Slow flow and bad water taste are also indicators for a new filter.
Shipping & returns

- Free standard shipping on all orders
- Express shipping options available at an additional cost
- Orders processed and shipped within 2-3 business days
- 30-day return policy for a full refund or exchange if product is not used and in original packaging
- Return shipping covered for defective products only

Care guide

While the bottle itself is dishwasher-safe (top rack only), we recommend hand washing to maximize its lifespan and protect the cap threads from potential wear.

IMPORTANT: Never put the filter in the dishwasher—it will be permanently damaged.

Hand Washing (Recommended):

  1. Remove the cap and filter
  2. Wash with lukewarm water and mild detergent
  3. Rinse thoroughly
  4. Repeat if necessary

Dishwasher Instructions:
If using a dishwasher, remove the cap and filter first, then place the bottle on the top rack only. Note that high heat settings may affect the bottle over time.

Warranty Policy

Our warranty covers defects in materials and workmanship of our products for a one year period from the date of purchase. Warranty does not cover damage due to use, misuse or abuse of products. It also does not cover damage from use other than specified in the product brochure (included with each product). Due to potential exposure to protozoa, bacteria and viruses, ÖKO reserves the right to refuse handling of used products.

ÖKO DUO bottle being dipped into a mountain creek

The Peak Performance
Water Bottle.

Every creek, tap and spigot on the route is already a refill.

ÖKO DUO purifier straw seated inside the bottle
1

Fast-Flow
Filter Bottle

Drinking through the detached ÖKO DUO purifier straw at the water's edge
2

Detach The Straw

Virus-Grade
Survival Straw

Filling the ÖKO DUO from a creek

Fill Anywhere.

Creek, spring, campground spigot, questionable hotel tap. 99.99% of viruses and 99.999% of bacteria removed, so the source stops being a decision you have to make.

200+

Contaminants
Removed

It Stays Where
You Put It.

A moulded non-slip rubber base grips wet rock, a tailgate, or a desk, and keeps the bottle quiet every time you set it down.

Non-slip rubber base of the ÖKO DUO bottle

Uncompromising Filtration.

Purifying without stripping out the essential minerals that make water taste right.

View Lab Reports
PFAS icon

PFAS / Forever Chemicals

99.9%

Avg. Reduction

Microplastics icon

Microplastics

As Small As

1µm

Smallest Particle Removed

Bacteria icon

Bacteria

5-Log Reduction

99.999%

Avg. Reduction

Virus icon

Broad Assay Viruses

99.99%

Avg. Reduction

Others Just Filter. ÖKO Purifies.

Most filters just block contaminants, forcing water through a dense mechanical barrier. ÖKO is different: our electro-adsorptive media attracts and retains contaminants while letting clean water flow freely through. The result is faster flow and cleaner water.

ÖKO's electro-adsorptive media attracting and retaining contaminants while water flows through
1

Mechanical Microfiltration

Particles are physically blocked at the membrane surface.

Rust Sediment Dirt
2

Electro-Adsorption

Contaminants are drawn in magnetically and captured, while pure H2O passes through.

Bacteria Viruses PFAS Microplastics + Much More

The Complete Solution.
Anywhere.

How We
Compare

ÖKO logo
Lifestyle Filtration icon Lifestyle Filtration
Outdoor Press icon Outdoor Press
Filtration Straw icon Filtration Straw
No Setup Required
99.99%+ Virus & Bacteria Removal
Fast-Flow Filtration
Bottle And Standalone Straw In One
Water Sharing, No Suction Required
Cap and stainless steel straw lifted out of the ÖKO DUO bottle
3

Everyday
Insulated Bottle.

Fill with your favorite drink, hot or cold.

Hot Coffee
Fresh Juice
Ice Cold

Eliminate The
Bottled Water Tax.

Annual savings icon

$800+

Annual Savings

Switching off single-use plastics pays the bottle back many times over.

Gallons per filter icon

200

Gallons Per Filter

One replaceable purifier straw covers a full year at about a litre a day.

NSF-accredited lab tested badge

NSF-Accredited Lab Tested

Independently verified for safety, clarity, and quality.