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4-Stage 0.1 Micron Ultra-Filtration Under Sink / Inline Water Filtration System with No-Pressure Chrome Faucet

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  • 0.01-micron ultra filtration + KDF + carbon + PP
  • Removes up to 99% of lead, chlorine, heavy metals, and more
  • It does not reduce TDS. Check out our RO systems for TDS removal.
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How to Get It

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Product Overview

Filter Type
Fitting Size
Top Contaminants Filtered
Lead
Chlorine
Iron
Number of Filters
Warranty
Twist and Lock
Simpler and more compact than Reverse Osmosis systems, the CU-A4 is an excellent choice for most general water filtration applications. The advanced 4-stage design of the CU-A4, featuring a unique combination of Activated Carbon, Ultra Filtration and KDF filters, removes a wide variety of unhealthy contaminants, including lead, arsenic, iron, nickel, chromium, cadmium, calcium, aluminum, mercury, chlorine and chlorine treatment by-products, pesticides, hydrogen sulfide and other organic compounds. You experience safer, healthier and better-tasting water, without the hassle, expense and negative environmental impact of bottled water. It is very easy to install and maintain - only requiring occasional filter replacement. The high-capacity, high-performance filters last up to twice as long as other filters and provide maximum water flow - a difference you'll notice when you turn on the faucet. A beautiful lead-free faucet included with the system is usually mounted on the counter as the primary source of drinking water, but with a wide range of optional parts and accessories, the CU-A4 easily adapts to fit nearly any refrigerator or ice maker connection. Our push-to-connect fittings and color-coded tubing simplify the installation process and minimize the possibility of leaks. Perfect for RVs, apartments or where space is at a premium, the CU-A4 is the best, most economical and flexible choice for clean, fresh, great-tasting water instantly.
  • Superior 4-stage multipurpose water filtration system for safer, healthier, better-tasting water. The advance 4-stage design, which includes both Ultrafiltration and KDF/GAC stages removes up to 99% of 700+ contaminants including LEAD, VOC, Chlorine while keeping healthy minerals. Note: This system does not reduce TDS as Reverse Osmosis system does.
  • 0.1 micron ultrafiltration (UF) stage removes up to 99% of most problematic pollutants such as chlorine and chlorine treatment by-products, lead, arsenic, and much more, while retaining healthy minerals
  • Simple, compact and flexible, the CU-A4 provides highly effective water filtration for any number of clean-water needs - at the sink, in the refrigerator, for coffee makers and more, with no storage water tank and no waste water, the CU-A4 is perfect even for RVs
  • Designed for high reliability, maximum flow rate and low maintenance, the CU-A4 uses High capacity cartridges that last up to twice as long as similar products. can be installed inline and used as a fridge filter
  • All filters, tubing and other water-contacting parts are manufactured to comply strictly with FDA and NSF/ANSI standards for safety and water quality, simple to install and simple to maintain, CU-A4 easy-twist cartridges simply twist on and off
  • Note: if you plan to use the CU-A4 as an inline filter without the included air-gap faucet, your incoming water pressure needs to be 40 PSI or below, if it is above that, a 40 PSI pressure regulator (APR40) should be installed on the input line to keep the pressure on the system at 40 PSI or below, please contact us if you plan to "tee off" the pure water line and connect it to your fridge, as you would need a regular RO faucet along with a pressure regulator



Additional Resources

From the Manufacturer

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4-Stage 0.1 Micron Ultra-Filtration Under Sink / Inline Water Filtration System with No-Pressure Chrome Faucet
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BrandGEISPRINGKOHLERBrita
NameUnder Sink Dual Flow Water Filtration System4-Stage 0.1 Micron Ultra-Filtration Under Sink / Inline Water Filtration System with No-Pressure Chrome FaucetAquifer Under-Sink Double Cartridge Water Filtration SystemRedi-Twist Purifier 3-Stage Drinking Water Filtration System
Price
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Add to Cart to See Price
$16982
$21670
Ratings
(190)
(74)
(39)
(25)
Contaminants FilteredLead, ChlorineLead, Chlorine, IronLead, Chlorine, Bacteria, Copper, Fluoride, IronLead, Chlorine, Bacteria
IncludesHardware,Installation kitFaucet,FilterFilterFaucet,Hardware,Installation kit
House Hold SizeUnspecified5-6 people3-4 people5-6 people
Number of Stages2 Stage4 Stage1 Stage3 Stage
Filtration MethodCarbon BlockCTO,Carbon Block,Coconut Shell Carbon,GAC,KDF,SandCoconut Shell CarbonHollow Fiber Membrane
Ease of InstallDrilling RequiredEasy InstallEasy InstallDrilling Required
FeaturesNo additional featuresTwist and lock designTwist and lock designAutomatic shutoff
Replacement Filter TypeUnder Sink Replacement FiltersUnder Sink Replacement FiltersUnder Sink Replacement FiltersUnder Sink Replacement Filters
Number of filters included2423
View ProductView ProductView ProductView Product

Specifications

Dimensions

Fitting size (in.)
0.25
Product Depth (in.)
4
Product Height (in.)
13.5
Product Width (in.)
15

Details

Application Type
Food Service,Inline,Office,RV,Water Treatment
Bacteria Reduction (%)
0
Chlorine reduction (%)
99
Color/Finish
White
Contaminants Filtered
Lead, Chlorine, Iron
Copper Reduction (%)
0
Ease of Install
Easy Install
Features
Twist and lock design
Filtration Method
CTO,Carbon Block,Coconut Shell Carbon,GAC,KDF,Sand
Fitting style
Quick connect
Fluoride Reduction (%)
0
House Hold Size
5-6 people
Includes
Faucet,Filter
Iron Reduction (%)
95
Lead reduction (%)
99
Maximum feed water pressure (psi)
50
Maximum feed water temperature (F)
100
Maximum filtered water flow (gallons per min.)
0.56
Minimum feed water pressure (psi)
20
Minimum feed water temperature (F)
40
Number of filters included
4
Number of Stages
4 Stage
Pack Size
1
Product Weight (lb.)
6
Replacement Filter Type
Under Sink Replacement Filters
Returnable
90-Day
Water Filtration System Type
Under Sink

Warranty / Certifications

Certifications and Listings
No Certifications or Listings
Manufacturer Warranty
1 Year

Questions & Answers

Typical questions asked about products:

  • Is the product durable?
  • Is the product easy to use?
  • What are the dimensions of the product?

Customer Reviews

  • 4.5
    out of 74 reviews
  • 79%recommend this product
Filter by:
Showing 1-10 of 74 reviews
Excellent system
Easy to install, great flow and good tasting water, system works very well. Much simpler and easier/cheaper to maintain compared to an RO system, filters are reasonably priced and long lasting. Was split between this system and a comparable Watts system, happy with our choice. Also occupies less space than an RO system, fit under our sink easily and a valve was supplied with the kit to adapt to existing plumbing. Faucet looks nice in chrome and is of high quality, has a very smooth action and nicely weighted handle. iSpring customer service is top notch, had a defective fitting, Francis from iSpring was quick to respond and got the parts out to me within a few days. Very satisfied overall.
by
    • Recommended
    Ispiring 4 Stage
    Replaced an old RO unit that had a tank and 1 to1 waste water to filtered water ratio. The old system 12 years ago was $546.00. It was installed by the plumbing company used by the general contractor we hired to build our new home. The removal was simple. The new installation was simple but had challenges due to how the plumber chose to connect the water feed to the old system. A brass 3/8 compression tee with a 1/8" FM NPT outlet. I found a brass adapter 1/8" M NPT to 1/4" FM NPT. Connected the plastic shutoff value 1/4" M NPT to this brass adapter. The shutoff value also had a 1/4" tube connection. See photos. Once I had acquired the correct connections the install took 30 minutes. I am well pleased with the new tankless Ispiring RO unit with no waste water.
    by
    • Recommended
    Replaced an old RO unit that had a tank and 1 to1 waste water to filtered water ratio. The old sy...
    Replaced an old RO unit that had a tank and 1 to1 waste water to filtered water ratio. The old system 12 years ago was $546.00. It was installed by the plumbing company used by the general contractor we hired to build our new home. The removal was simple. The new installation was simple but had challenges due to how the plumber chose to connect the water feed to the old system. A brass 3/8 compression tee with a 1/8" FM NPT outlet. I found a brass adapter 1/8" M NPT to 1/4" FM NPT. Connected the plastic shutoff value 1/4" M NPT to this brass adapter. The shutoff value also had a 1/4" tube connection. See photos. Once I had acquired the correct connections the install took 30 minutes. I am well pleased with the new tankless Ispiring RO unit with no waste water.
    by
      • Recommended
      Sent me a used product
      The box was perfectly new and intact, but this is a previously used product.
      by
        Why do you sent used item????
        I paid for brand new filtration, but seller sent used filtration!!! see pictures!it has human hair!!!!
        by
          Easy to install. great tasting water
          Very simple to install. Perfect where there is a lack of space for a tank. Water pressure is great. Came with a water leak detector which i wasnt expecting.
          by
            • Recommended
            Excellent product and excellent customer support!
            This product was very easy to install and works great. Francis at iSpring customer support helped me with any questions I had. Highly recommend!
            by
              • Recommended
              Good product, great customer service
              Pros: Not wasteful like R/O system. We have great city tap water, but the wife...well she has particular tastes and fears. The water comes out with a perfect mouth feel; no "tap taste" or chlorine smell, and I'm not a connoiseur by any stretch.There is a helpful youtube video out there to help you install it, if the handbook is not enough. Drilling the hole in your kitchen counter is the hardest part. You need to have the right bit, the right tools, and the right spot--I would understand if people don't feel comfortable here. Cons: After 15 months using it the faucet broke. The handle spins all the way around, not closing the valve if water is running, nor will it open the valve if it is closed. Luckily I reached out to iSpring and they are shipping me an entirely new manifold free of charge under the 3-year warranty. Hopefully I just got a faulty one. I haven't received the new one yet, but will revise my review if it doesn't solve my problem. Thank you to Nick at iSpring for helping me so far.
              by
                • Recommended
                3 found this review helpful
                This is the best filter I could find, that isn't a water wasting R/O, after a ton of research, t...
                This is the best filter I could find, that isn't a water wasting R/O, after a ton of research, this is the best filter system for under counter IMO. The instructions that come with it are a joke. I was able to go online and find instructions that where much more coherent. Came with everything I needed to connect to my water lines under the sink took me 30 minuets to install.
                by
                • Verified Purchase
                • Recommended
                15 found this review helpful
                Had to purchase dual ended quality quick connects and other...
                Had to purchase dual ended quality quick connects and other lines in case they were the problem. But quick connects were problem. All connectors on ispring rack were sufficient, but must force lines deep to not leak. Cost extra $70 worth parts. Water quality is awesome...love the faucet. Have sweating or slight leak 1st filtration canister but so so very minute. Love clean water...must connect direct to main water line under sink so had to get a special 3 way plumbing parts put together. Hard work but Worth clean water. High volume water on tap. If your not a plumber like me...hire someone. Would buy again and recommend.
                by
                • Verified Purchase
                Showing 1-10 of 74 reviews