Under Sink for RO structured water
Under Sink Structured Water System
Natural Action Home Unit Installs easily Structured Water
Promotional infographic for an under sink water filter system, showing illustrated components including an RO system, a passive system canister, and a quick-connect faucet setup with water flowing into a glass.

Under Sink Structured Water System

Regular price $599.00
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  Vortex-Flow Technology for Your Kitchen Faucet

Better Water Starts Where You Use It Most.

From your morning glass of water to coffee, tea, and cooking, your kitchen is at the center of your daily water routine.

The Natural Action Under Sink Structured Water System (HD-9) brings our signature vortex-inspired flow-form technology directly to your kitchen faucet.

Installed beneath your sink, the HD-9 guides water through engineered internal pathways as it flows to your faucet.

No electricity. No chemicals added. No replacement structuring filters.

One Simple Upgrade. Everyday Water, the Natural Action Way.

Why Choose the HD-9 Under Sink System?

  • Vortex-Inspired Flow Technology — Guides water through engineered spiral-flow pathways inspired by water movement in nature.

  • Everyday Kitchen Convenience — Enjoy the same passive water-structuring process whenever you use the connected faucet.

  • Designed for Drinking & Cooking — A convenient addition to your daily drinking-water, coffee, tea, and food-preparation routine.

  • Works with Compatible Existing Plumbing — Installs inline beneath your sink without requiring a countertop device.

  • No Electricity or Batteries — Powered entirely by water flowing through the unit.

  • No Replacement Structuring Filters — No disposable cartridges or recurring filter purchases.

  • Made in the USA — Backed by a 10-Year Limited Warranty and 90-Day Satisfaction Guarantee for eligible purchases.

The Benefits of Structured Water at Your Kitchen Sink

Make Every Glass Part of a Better Water Routine.

A More Enjoyable Drinking-Water Experience

Many Natural Action customers choose structured water because they are interested in how their drinking water tastes and feels.

The HD-9 introduces vortex-inspired water movement at the point where you use water most often.

Taste and mouthfeel are subjective, and specific improvements are not guaranteed.

Support Your Daily Hydration Routine

Having convenient access to drinking water can make it easier to maintain consistent hydration habits.

With the HD-9 installed beneath your kitchen sink, water passes through the Under Sink Structured Water System automatically whenever you use the connected faucet.

No separate pouring device or additional preparation is required.

A Different Approach to Coffee, Tea & Cooking

Water is an essential ingredient in coffee, tea, soups, and everyday cooking.

The HD-9 lets you incorporate Natural Action's passive vortex-flow process into your kitchen routine without adding treatment chemicals or minerals.

Vortex-Inspired Water Movement

Natural waterways often exhibit spiral movement and circulating currents.

Natural Action uses this design inspiration to create engineered flow pathways that guide water through a controlled vortex-inspired process.

A Long-Term Kitchen Upgrade

Unlike disposable water-treatment accessories, the HD-9 is designed as a permanently installed, passive plumbing component.

It requires no electricity, batteries, or replacement structuring cartridges.

From Your First Glass of Water to Your Last Cup of Tea.


How the HD-9 Works

Flow, Not Force.

The HD-9 uses specially designed internal flow-form geometry to guide water through a vortex-inspired pathway.

As water passes through the unit, it follows the engineered flow channels before reaching the connected kitchen faucet.

Three Simple Steps:

  1. Install the HD-9 inline with compatible under-sink cold-water plumbing.

  2. Turn on your kitchen faucet as usual.

  3. Water passes through the Under Sink Structured Water System automatically whenever the connected line is in use.

No electricity. No chemical additives. No replacement structuring filters.

Important: Structuring Is Not Filtration

The HD-9 is a water revitalizer, not a water filter.

It does not remove chlorine, lead, PFAS, bacteria, or other contaminants, and it does not disinfect water.

If your drinking water requires contaminant reduction, use an appropriate certified filtration system before the HD-9.

Filter First. Structure Last.

LEARN THE DIFFERENCE BETWEEN STRUCTURED AND FILTERED WATER


Installation & Compatibility

Designed for Your Kitchen.

The HD-9 installs beneath your sink on a compatible cold-water supply line.

For a typical drinking-water installation, the unit is positioned downstream of any required filtration so that water passes through the Under Sink Structured Water System before reaching the connected faucet.

Professional installation is recommended.

Product Specifications

Feature Specifications
Product Under Sink Structured Water System
Model / SKU HD-9-US
Technology Passive vortex-inspired flow-form engineering
Primary Application Kitchen drinking-water and food-preparation faucet
Installation Inline beneath sink
Connection Size 1/2-inch NPT
Water Line Compatible cold-water line
Electricity Not required
Replacement Structuring Filters None
Chemicals Added None
Contaminant Filtration Not provided
Country of Manufacture USA
Warranty 10-Year Limited

Installation note: Verify fitting orientation, available installation space, water pressure, and plumbing compatibility before installation. Use the manufacturer's installation instructions.

VIEW HD-9 INSTALLATION INSTRUCTIONS

Simple Care & Maintenance

The HD-9 does not require replacement structuring cartridges.

Once installed, inspect plumbing connections periodically and address any leaks or changes in flow.

Continue maintaining any separate filtration system according to its manufacturer's instructions.


Which Natural Action System Is Right for You?

From One Glass to Your Entire Home.

Already Have Reverse Osmosis?

HD-9 Post-RO Inline Structured Water System

If your kitchen uses reverse osmosis, Natural Action offers a dedicated post-RO model designed for compatible 1/4-inch quick-connect tubing.

EXPLORE THE POST-RO SYSTEM

Want Filtration and Structuring Together?

HD-9 + Multipure Aquaversa

Combine under-sink drinking-water filtration with Natural Action's passive vortex-flow technology.

The Multipure system addresses specified contaminants, while the HD-9 provides a separate water-structuring stage.

EXPLORE UNDER-SINK FILTRATION + STRUCTURING

Want Structured Water Throughout Your Home?

Whole Home Structured Water System (HD-24)

Bring Natural Action's vortex-inspired technology to compatible water outlets throughout your home.

EXPLORE WHOLE-HOME STRUCTURED WATER

Not Sure Which System Is Right for You?

Take the 60-Second Natural Action Water Assessment.

Answer a few questions about your water source, current filtration, and goals to find a recommended starting point.

TAKE THE FREE WATER ASSESSMENT


Buy with Confidence

Made in the USA

10-Year Limited Warranty

90-Day Satisfaction Guarantee

Natural Action Technical Support

Warranty and satisfaction guarantee are subject to published terms.


Frequently Asked Questions

What does the Under Sink Structured Water System do?

The HD-9 guides water through engineered vortex-inspired flow pathways as water passes through the unit before reaching the connected kitchen faucet.

What are the benefits of the HD-9 Under Sink System?

The HD-9 provides convenient, passive vortex-flow technology for everyday kitchen water use. It requires no electricity, adds no chemicals, and has no replacement structuring cartridges. Individual experiences with water taste or feel may vary.

Does the HD-9 improve the taste of drinking water?

Some customers report a difference in taste or mouthfeel. These experiences are subjective, and the HD-9 does not remove taste- or odor-causing contaminants. Use appropriate filtration if contaminant reduction is needed.

Does the HD-9 filter contaminants from water?

No. The HD-9 does not remove chlorine, lead, PFAS, bacteria, or other contaminants. It is a water-structuring device, not a drinking-water filter.

Can I use the HD-9 with an existing water filter?

Yes, when the plumbing and equipment are compatible. The HD-9 is generally installed downstream of appropriate filtration, allowing water to be filtered first and then pass through the revitalizer.

Can I install the HD-9 after a reverse osmosis system?

Natural Action offers a dedicated HD-9 Post-RO model with 1/4-inch quick-connect fittings for compatible reverse osmosis systems. Choose the model that matches your plumbing configuration.

Does the HD-9 require electricity or replacement filters?

No. The HD-9 operates through water flow and requires no electricity, batteries, or replacement structuring cartridges.

What size connections does the HD-9 use?

The HD-9-US model uses 1/2-inch NPT connections. Confirm the fitting orientation and plumbing compatibility before installation.

Is professional installation recommended?

Yes. A qualified plumber can verify the correct installation location, fitting compatibility, and leak-free connections.

Is the HD-9 covered by a warranty?

Yes. The HD-9 is backed by Natural Action's 10-Year Limited Warranty and a 90-Day Satisfaction Guarantee for eligible purchases, subject to published terms.


Better Water Starts at Your Kitchen Sink.

One Faucet. Every Glass. Natural Action.

Bring vortex-inspired flow technology into your daily kitchen routine with the Natural Action HD-9 Under Sink Structured Water System.

Add to Cart. Make Natural Action Part of Every Day.

Natural Action — It's Water, The Way Nature Intended.

 

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  • 5 stars: 22 (100%)
  • 4 stars: 0 (0%)
  • 3 stars: 0 (0%)
  • 2 stars: 0 (0%)
  • 1 star: 0 (0%)
K
Kris Gethin
If I could give 10 stars, I would

I didnt know what to expect when I had the under the sink filter fitted but within the first 6 weeks I had more sustained energy, better skin and better workouts. I drink around a gallon of water per day with combined with electrolytes, creatine, my pre-workout, protein shakes, etc, and I honestly feel I was getting so much more efficacy from them. I truly believe that allowing the filter to structure my water over my mitochondria has helped my energy levels noticeably

A
Ashley
International Buyer Review

The customer support offered by this company has exceeded all my expectations.  Top notch service and customer-centric.

This is very crucial for overseas buyers like myself as there is this worry that we do not have anyone to turn to, to resolve any issues which pop up after the purchase.  I took a chance to make my previous purchases and I am glad I did. 

In June, my structured water device leaked. It was 9 years old. The company immediately shipped a replacement at their cost using UPS to my country with minimal questioning. I was so thankful for their prompt and thoughtful assistance.

I will not hesitate to recommend my friends and family to shop here if they are in need of a structured water device or water filtration system. And I intend to return to shop with them in the future.

S
S. Cash

I've been structuring water now for over a year me, my cats and my plants and my small splash pool. When I first gave a bowl to my cats I tested it by putting it alongside a bowl of non-structured water. They went to the structured water bowl to drink.
I notice a difference in the taste. Structured water just tastes cleaner and more refreshing.
Another notable difference is in the structuring of my pool water. It requires much less chlorine for longer periods of time.

L
Liala A.

I ran my swimming pool for 7 months using a dedicated unit installed between the pump and filter. Using the unit ended the extreme algae growth and balancing problems that were ongoing issues over the previous 20+ years . With the unit installed, the pool water was crystal clear, soft and blue and the water proved to be self balancing. This was most evident after rainfalls, which were unusually frequentl and sometimes torrential, and our many pool parties. I added 4 gallons of household bleach (5% sodium hypochlorite) over a 3 week period of intense heat, to remove algae that was growing on the plaster walls. I.used and no other agents or devices to support the water quality.

A
Anonymous

Looking forward to seeing the effects of the device in the pool. Have not had a chance to have it installed yet.

D
Dan

Easy to install, no leaks... so far so good. As with any new product, I'll want to run it for a couple months to really give it a full test, but I like what it's doing for my water.

D
Dave G.

Great combo with other products! Pure and structured!

K
K. Bear

We are very happy with our structured water devices! These devices are easy to install and the service is friendly and efficient. I have just bought another single tap for my parents. Highly recommended!

K
Keith E.

This unit along with a Frizzlife Under Sink Water Filter not only made our water taste amazing, it shifted the PH of the water from acidic to alkaline.

C
Corwin W.

We've owned a hand-held NAT structured water filter for years, and have experienced the results first-hand, as well as introducing their technology to friends and family. It was only a matter of time before we upgraded and installed this one under our sink, and it significantly reduces our structuring time while keeping the water smooth, energized and happy. (yes, water can be happy... Google the recent scientific breakthroughs showing that water has memory!) Not only are we thrilled with the structuring, but NAT was able to ensure we received the product as expected and we experienced immediate and above-and-beyond customer service. What a great company. Our only other concern before buying this was that is might have been a counterfeit seller because of such limited reviews, but in good news this is the legitimate company and the product is 100% authentic. Thanks NAT!

G
Gary Grant

I have a saltwater pool that uses city water, so I went to Natural Action Technologies Structured Water web site and ordered the pool version of what I have in my home. Immediately, my pool water turned to crystal clear like never before. It’s very hot (105 to 117) in the Palm Springs, Calif. area, so extra chlorine is needed to keep the proper ph. It’s been 3 weeks and my pool man is adding 1/3 less chlorine and the ph is still stable. Every week we continue to use less chlorine and now,  the water is invigorating and inviting me to leap in. What a delightful turnaround of my pool water.   I attached pictures of the unit attached to my pool system and made a canvas cover to protect it from the sun.
Thank you Natural Action for inventing this technology…

C
Chris B.

Thank you for introducing me to the Vortex Structured Water products. I love the portable structuriser. I take it with me everywhere I go for myself, family and friends. I love how much easier it is to drink water and how much quicker it seems to be absorbed from my stomach. For example, I can easily drink 0.5 to 1 Litre of water and exercise within 15mins at a very high level aerobically without any stomach discomfort. If I drink water straight from the tap, it rumbles around in my stomach for a long time (maybe 30 – 60 mins) before I can exercise comfortably. The difference is amazing.

C
Corwin W.

We've owned a hand-held NAT structured water filter for years, and have experienced the results first-hand, as well as introducing their technology to friends and family. It was only a matter of time before we upgraded and installed this one under our sink, and it significantly reduces our structuring time while keeping the water smooth, energized and happy. (yes, water can be happy... Google the recent scientific breakthroughs showing that water has memory!) Not only are we thrilled with the structuring, but NAT was able to ensure we received the product as expected and we experienced immediate and above-and-beyond customer service. What a great company. Our only other concern before buying this was that is might have been a counterfeit seller because of such limited reviews, but in good news this is the legitimate company and the product is 100% authentic. Thanks NAT!

M
Mark C.

I am very pleased with the quality of softness this unit has added to my water. I feel better and enjoy the purity this unit creates. Thank you!

K
Kurt C.

I have continued my own home experiments drinking structured water which has me in such a state of euphoria, I couldn't begin to explain it. My skin was extremely dry — so much so, that my knuckles were split open. They are healed and my skin is smooth as a babies bottom in just a few days. Tap water tastes like bottled water. I have more energy than I did as a teenager. I am even putting some on the wrinkles under my eyes which are fading away. I am adding a life coaching service to my website which will give me a great platform for promoting your devices. Have a great day!

N
Nimueh

Since I began with Structured water about two weeks ago, I have sponged off two of my beloved cats, each in her distinct area of chronic irritation (despite vast and creative other approaches – vet, holistic and energetic), one having been treated for over four years.
Both cats showed immediate improvement – in one, general itchiness subsided (after months of this hassle); and in the other, a runny eye lessened (and she was looking at me again for the first time in about two years, instead of turning her head away).
I am continuing to sponge off these two kitties, as well as provide Structured Water for all drinking purposes. Both cats’ conditions are significantly better in just a short time!
Further, all my five cats are getting along better together, noticeably so! They weren’t too raucous, before, but it is very loving and peaceful here now! And also they see more cognitive generally, and more communicative with me.
I feel more positive and motivated to accomplish my daily goals, and I feel my longer term visioning power has increased. My aura feels enhanced and stronger! It seems more positivity is coming into my life, and it’s connected with having Structured Water in and around me!
Thank you!

F
Francoise A.

I was not an insomniac person, but very often if I would be awakened by any noise or the urge for a little pee, it would practically ALWAYS take me a very, very long time (between, one to two hours) to fall asleep again. Well, after 4 days – yes! Only FOUR days! – I was falling asleep again within 3 to 10 minutes maximum! I was really very surprised to have this result in such a short time. And, do believe me, there was nothing to do with the placebo effect, because I never thought of a result linked with my sleep. In addition, I definitely felt more energetic even as I am still very energetic for my ‘passport age’! (74 and a 1/2), but I am more of a 54 and a 1/2!

S
S. Cash

I've been structuring water now for over a year me, my cats and my plants and my small splash pool. When I first gave a bowl to my cats I tested it by putting it alongside a bowl of non-structured water. They went to the structured water bowl to drink.
I notice a difference in the taste. Structured water just tastes cleaner and more refreshing.
Another notable difference is in the structuring of my pool water. It requires much less chlorine for longer periods of time.

K
K. Springer

I was skeptical but this is crazy. I had it installed so that my water first goes through a reverse osmosis system them through the structure unit last. This water is crazy. It seems alive. I’m telling you, it moves. Hold it to light and it sparkles like champagne. I watered my plants the first day, then left town. Upon my return... I walked into a jungle. All the plants had grown so much in just three days. I actually can not use this water every time on my plants because all 23 plants out grew their pots and I can’t keep repotting everything. I also had to fertilize because they grew so fast they ate everything from their soil. So then I installed the shower structure unit in my shower. The difference in my skin and hair are very noticeable. And the water tastes really good. My friends filled up glass jars as they are leaving. Best purchase ever but, I do recommend a water filter system also to remove the chemicals first.

D
D. Bennet

It helped me enjoy drinking water again. Went from 2-4 cups a day max to 2-3 liters a day. My body absorbed the water using your unit rather than going to the gents 10 times a day when I attempted to drink 2 liters + per day in the past Massive change. It tastes better! Made me feel more relaxed and less jittery for some reason. I can’t explain this. It made me calmer somehow… in the same way that meditation calms my mind, this “calmed my body” somehow by drinking more vortexed structured water. I have attempted to drink 1-3 liters a day in the past but my body didn’t like it – the taste and bloated feeling. This is easy to drink, no bloating! Ate much less food as drinking more water and light dinners so I seem to save food and money! I am convinced 100%. Big change!

A
A.G.

After hooking up the under sink unit that I purchased from you, I am convinced that what you say is true. It has empowered me to be at my best 24/7. I run a small electronics company and most days are very challenging.
My wife of 34 years seem to have grown in different directions. I was pretty normal when we got married but she thinks I am crazy now. So I started drinking the water and she has also. WOW, now I stay full of love most of the time, and it appears to have assisted my wife also. At this point in time I would like to spread this around.
I think I may be addicted, I get out of the shower and have to go to the basement and get some structured water. I wake up at night thirsty, I drink structured water. I love the way I feel. Honestly the water has helped me become a beacon of light 24/7.
THANKS

M
Mark C.

I am very pleased with the quality of softness this unit has added to my water. I feel better and enjoy the purity this unit creates. Thank you!