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iSpring CU-A4 4-stage GAC Under Sink Water Filtration System with Brushed Nickel Faucet

Name: iSpring CU-A4 4-stage GAC Under Sink Water Filtration System with Brushed Nickel Faucet
Brand: iSpring
SKU: 5017193465
Price: 342.98 USD
Availability: InStock
Rating: 4.7 (43 reviews)

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4.7

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iSpringCU-A4 0.01um Ultra-Filtration Under Sink Water Filter System, Tankless 4-Stage High Capacity, Remove 99.99percent Contaminants, Quick Filter Change 4-stage GAC Under Sink Water Filtration System with Brushed Nickel Faucet

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Advanced 4-Stage Filtration: The iSpring CU-A4 effectively reduces chlorine, lead, heavy metals, VOCs, and harmful contaminants, delivering clean and safe drinking water straight from your tap.
Improved Taste & Odor: Enjoy fresh, crisp water by removing unpleasant taste, chlorine smell, and chemical residues, making it ideal for cooking, beverages, and direct consumption.
Compact & Easy to Install: Designed for under sink use, the CU-A4’s space-saving build fits neatly in kitchens, apartments, or RVs; DIY-friendly installation requires no plumbing experience.
Durable & Reliable Performance: Constructed with high-quality materials, the CU-A4 ensures consistent filtration and dependable long-term use, providing better water at your convenience.
Includes Replacement Filters (F4-CUA4): Bundle comes with a complete filter set for up to 1 year of use, ensuring continuous fresh water without the hassle of frequent reorders.

General
Color/Finish Family	White	Installation Type	Seperate faucet
Manufacturer Faucet Finish	Brushed Nickel	Min Feed Water Temperature (Fahrenheit)	40
Series Name	CU-A4	Max Feed Water Temperature (Fahrenheit)	100
Package Quantity	1	Filtration Method	GAC
Package Contents	Water filter system, filter set, faucet, tubing, feed Water Adapter	Number of Filters	4

Dimensions
Diameter (Inches)	2.5	Length (Inches)	15
Height (Inches)	13.5	Weight (lbs.)	5
Household Size	3-4 people	Width (Inches)	4

Features
Faucet Included	Yes	Reduces Micro-Organisms	No
Filter Life (Months)	6	Reduces Pharmaceuticals	No
Flow Rate (GPM)	.5	Reduces Turbidity	Yes
For Drinking Water	Yes	Reverse Osmosis Filtration	No
Lowe's Exclusive	No	Stage	4-stage
Recommended Use	All water types	Total Contaminants Reduced	99
Reduces Chemicals	Yes	Total Dissolved Solids (Percentage)	0
Reduces Chlorine Taste and Odor	Yes	Reduces Chloramine	Yes
Reduces Cysts	Yes	Micron Rating	.01
Reduces Iron	No	Reduces Bacteria and Viruses	No
Reduces Lead	No	Reduces PFOA/PFOS ("Forever Chemicals")	Yes
Reduces Mercury	Yes

Warranty
Warranty	1-year

Certifications
CA Residents: Prop 65 Warning(s)	No	Safety Listing	Not safety listed

Compatibility
Replacement Filter Model #	F4-CUA4

Miscellaneous
UNSPSC	40161500

Check out the Best Selling Under Sink Filtration Systems on Lowes.com

Review

4.7 out of 5

43 Reviews

3 Star

2 Star

100% Recommend this product

Ratings may include incentivized customer reviews.

What Customers Are Saying

Customers overwhelmingly praise the water filtration system for exceptional taste improvement, comparing it to bottled or spring water while retaining beneficial minerals. Most highlight straightforward installation completed in under an hour without plumbing experience needed. The compact under-sink design with tankless operation, quiet performance, and fast water flow appeal to many. Reviewers appreciate low maintenance with filter replacements every six months. A few report difficulty locating replacement filters or minor initial cloudiness, though these issues resolve quickly with flushing or support assistance.

Customer review summary generated by AI, including incentivized reviews.

43 Customer Reviews

Sort By

Great Value and Quality

Would Recommend

Sean was really helpful and responsive to an inquiry. System came quickly. Water quality is great! My family is enjoying this product and we are looking to purchase an additional unit for the farm. Thanks ISpring!

Snowbaby76August 29, 2025

From iSpring Water Systems

This is a great filter system. My wife has multiple chemical sensitivities and this filter works very well for her. It is also very easy to replace. I usually have a set in storage and when I change them out, I buy a new set, ready to go.

OrlanDecember 3, 2023

From iSpring Water Systems

I like these filters a lot, they do a good job and are super easy to replace. My wife has multiple chemical sensitivities and this filter works very well for her. I like to keep a spare set on hand and then when I replace, simply order a set immediately for the next time.

OrlanDecember 3, 2023

From iSpring Water Systems

This is the second CU-A4 system that I have put into two different fifth wheels and they are great. Most tap water taste so bad to me I can't stand to drink it, but these purification systems are great and works great in a RV. I highly recommend to everyone and especially RVers.

JimApril 30, 2022

From iSpring Water Systems

Is it discontinued ? It's out of stock everywhere Also after over 6 months of use, I still get a slight layer of oil from the faucet. Keep in mind that I flushed 15 gallons the 1st time I used it, but still, it releases oil with the water.

SamFebruary 22, 2021

From iSpring Water Systems

I have been buying springs water for drinking and even that has an inconsistent taste lately. So I decided to get a water filter system and after doing some research, I ended up with this one. Why? because it's compact, easy to install and change filters, and produce decent drinking water without waste any water.

DanielJune 8, 2020

From iSpring Water Systems

https://photos-us.bazaarvoice.com/photo/2/cGhvdG86aXNwcmluZ3dhdGVyc3lzdGVtcw/3073320e-3b0e-5e1f-bea0-cb2c6301bf84

I used to have an RO filter unit. This one lets the minerals in and water is tastes even better.

CarlosJune 7, 2020

From iSpring Water Systems

The taste is just as good as bought from the store. Much easier and nicer to use then the Brita pitcher we've been using for 2 years.

PrescottJune 5, 2020

From iSpring Water Systems

I am happy that I made the move and put in in. It was not difficult to install and I am not particularly handy. Water tastes good.

StevenJune 3, 2020

From iSpring Water Systems

Very pleases with the purchase. The water definitely tastes a lot better. I installed this system by myself and I think this will be a good investment for the family.

AnonymousJune 3, 2020

From iSpring Water Systems

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