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Enjoy fast and free shipping on all orders over $89! Contact us (855) 424-4376


EWS - Reverse Osmosis Under-Sink 4-Stage

by EWS
Original price $ 749.25 - Original price $ 974.25
Original price
$ 749.25
$ 749.25 - $ 974.25
Current price $ 749.25
Choose a Model

True Protection From Toxic Contaminants.

World-class EWS water filtration and performance for the removal of chlorine, chloramine, pesticides, THMs, VOCs, obesogens, lead, cysts, rust, silt, sediment, heavy metals, fluoride, and much more. The ESSENTIAL reverse osmosis system offers real protection against dangerous contaminants, while meeting your individual preferences for taste and mineral removal.

Made in the USA

Maintenance-free for up to 1 year before filter replacement. Just change them out and go!

ESSENTIAL Reverse Osmosis System Options.

You have the option of upgrading at any time to ultraviolet (UV) protection (model #RO4-UV), which kills 99.99% of bacteria, viruses, and other microorganisms.

The RO4 At A Glance.

  • Four stages of advanced carbon filtration and high-capacity reverse osmosis membrane.
  • Any individual or family seeking the convenience and health of filtered water at the kitchen sink (or any sink).
  • For those with budgetary constraints that do not allow the opportunity to filter the entire home.
  • City water or well water*

Our Standards. Manufactured and Assembled in the USA.

All product and components are compliant for food and beverage contact and comply, meet or exceed all current and applicable standards without exception.

All EWS product has been independently tested by an accredited third-party laboratory to meet and/or exceed all relevant FDA, California State regulations, and NSF standards for all claims made regarding NSF/ANSI standards. All EWS product is No-Lead Compliant to California AB1953.


Serious Water Filtration: The ESSENTIAL is the first drinking water system designed to protect you and your family from the modern issues with water contamination. Better tasting water can be achieved simply and cheaply by letting water sit out, or by using an inexpensive carafe or faucet attachment. However, none of the contaminants have actually been removed – chlorine byproducts, chloramine, pesticides, dissolved lead, and other contaminants are still present in the water. The ESSENTIAL is serious water filtration for people who desire truly clean, truly healthy water without the water waste or flat taste of reverse osmosis.

Hassle-Free & Convenient. Enjoy clean, delicious water right at your kitchen or bathroom sink at any time with zero hassle.

Easy to Install & Use: Installs easily at any sink.

No Wasted Money. No Plastic Bottles: Replace expensive and wasteful bottled water with the healthy, filtered water from your ESSENTIAL filtered sink. You will save at least $500 every year in bottled water expenses, and prevent plastic waste in our landfills and oceans. Simply fill up your reusable glass or metal bottle at your sink and go!

*WELL WATER WARNING Well water is required to have independent, complete and proper testing of your well water to determine the proper course of action in order to specify the correct system(s).


  • Model #: RO4 and RO4-UV
  • Depth: 5"
  • Height: 16"
  • Width: 16"
  • Storage Tank: 11"x11"x16" (3.2 gallon capacity, other tank sizes available)

Depth: 5"
Height: 16"
Width: 16"
Storage Tank: 11"x11"x16" (3.2 gallon capacity, other tank sizes available)

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