--- product_id: 48256916 title: "CU-A4 0.01 Micron Ultra-Filtration Under Sink Water Filter System | Tankless 4-Stage High Capacity , Remove 99.99% Contaminants, Quick Filter Change with Chrome Faucet, White" brand: "ispring" price: "$424.85" currency: USD in_stock: true reviews_count: 13 category: "I Spring" url: https://www.desertcart.us/products/48256916-cu-a4-0-01-micron-ultra-filtration-under-sink-water store_origin: US region: United States of America --- # 0.01 micron ultrafiltration membrane Tankless, no wastewater design 4-stage advanced filtration system CU-A4 0.01 Micron Ultra-Filtration Under Sink Water Filter System | Tankless 4-Stage High Capacity , Remove 99.99% Contaminants, Quick Filter Change with Chrome Faucet, White **Brand:** ispring **Price:** $424.85 **Availability:** ✅ In Stock ## Summary > 🚰 Elevate your tap game with ultra-pure, mineral-rich water—because your health deserves the best! ## Quick Answers - **What is this?** CU-A4 0.01 Micron Ultra-Filtration Under Sink Water Filter System | Tankless 4-Stage High Capacity , Remove 99.99% Contaminants, Quick Filter Change with Chrome Faucet, White by ispring - **How much does it cost?** $424.85 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/48256916-cu-a4-0-01-micron-ultra-filtration-under-sink-water) ## Best For - ispring enthusiasts ## Why This Product - Trusted ispring brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Space-Savvy & Sleek:** Compact under-sink design with premium chrome faucet frees up cabinet space and elevates kitchen aesthetics. - • **Crystal-Clear Hydration:** Ultra-fine 0.01 micron hollow fiber membrane removes 99% of chlorine, heavy metals, and contaminants while preserving essential minerals. - • **Trusted Safety & Quality:** All water-contact parts meet NSF/ANSI standards, ensuring safe, clean water for your family’s peace of mind. - • **Eco-Friendly & Cost-Effective:** Tankless system means zero wastewater and up to 8,000 gallons of premium filtered water per filter cycle. - • **Effortless Installation & Maintenance:** Push-to-connect fittings and twist-on/off filters make setup and replacements a breeze—no plumbing pro needed. ## Overview The iSpring CU-A4 Ultra-Filtration Under Sink Water Filter System features a cutting-edge 4-stage filtration process including a 0.01 micron ultrafiltration membrane and KDF/GAC filters to remove up to 99% of chlorine, heavy metals, and other contaminants while retaining beneficial minerals. Designed for easy installation with push-to-connect fittings and twist-on/off cartridges, it requires no storage tank or wastewater, delivering up to 8,000 gallons of clean water. Its compact, tankless design and premium chrome faucet make it a stylish, space-saving addition to any modern kitchen, backed by NSF/ANSI certified components for trusted water quality. ## Description Product Description Protect your home and health with the CU-A4 Ultrafiltration Water System Not For TDS Removal Please note: This Under Sink water filtration system DOES NOT lower TDS value, instead it will keep minerals in your water. Leak-Free System Push-to-connect fittings and colorful coordinated tubings simplify the installation process and prevent leaking. Save More Space The iSpring CU-A4 Under Sink Water System can be mounted easily under sink, leaving you more space for storage and letting you filter water directly. Cost-Effective System Our ultrafiltration system offers a cost-effective and convenient way to enjoy clean, filtered water in the comfort of your home. Easy Installation and Maintenance The CU-A4 is designed to be simple to install and maintain. Push to connect fittings and color-coded tubing simplify the installation process. iSpring Twist On / Twist Off filter cartridges makes changing filters a snap. Everything needed is included in the package. Premium Complex Filter Superior Over Others The CU-A4 is the only filter in its class to offer Kinetic Degradation Fluxion (KDF) Media which adds an important additional layer of protection to control metals. WHY CHOOSE ISPRING CU-A4 WATER SYSTEM? How CU-A4 ultrafiltration water purification system provides better water? PP Sediment Filter: removes larger particles like rust, sand, dirt. Ultra Filtration membrane: can effectively removes all colloidal particles (0.01 to 1.0 microns) and some of the largest dissolved contaminants from water. KDF and GAC Filter: provides control of problematic contaminants, such as chloramine, hydrogen sulfide, heavy metals, (VOC), chlorine and more. Post Activated Carbon: increase the oxygen content of the purified water, and mainly improve the taste of the water. Review: easy to install equipment - My Experience with the iSpring CU-A4 Under Sink Water Filter I recently installed the iSpring CU-A4 under sink water filter, and I'm genuinely impressed. As someone who's always been a bit skeptical about the true efficacy of home water filtration systems, this unit has completely changed my perspective. First off, the installation was surprisingly straightforward. I'm no plumbing expert, but the clear instructions and well-organized components made the process relatively painless. Within an hour or so, I had fresh, filtered water flowing from my dedicated faucet. And what a difference it makes! The most noticeable improvement is in the taste and smell of the water. Our tap water, while generally safe, often had a slight chlorine odor and a somewhat metallic aftertaste. With the iSpring CU-A4, that's completely gone. The water is crisp, clean, and incredibly refreshing. It's truly a pleasure to drink, and I find myself reaching for water more often throughout the day. Even my coffee and tea taste noticeably better. I also appreciate the compact design of the unit. It fits neatly under my sink without taking up an excessive amount of valuable cabinet space, which is a huge plus in smaller kitchens. The dedicated faucet is sleek and unobtrusive, blending well with my existing fixtures. While I can't scientifically measure the contaminant reduction, the peace of mind knowing that my family is drinking water filtered through a reputable system is invaluable. The four-stage filtration process, including activated carbon and ultrafiltration, gives me confidence that we're significantly reducing chlorine, sediment, and other common impurities. In conclusion, the iSpring CU-A4 under sink water filter is an excellent investment for anyone looking to improve the quality of their drinking water. It's easy to install, produces great-tasting water, and offers genuine peace of mind. Highly recommended! Review: Worth it - great water and good after sales support even years on - Long time customer or iSpring. I've installed the american style system in my family homes in Canada and this system in my home in the UK. Their filtered water tastes as it should! I had an issue with the included tap/faucet leaking but iSpring sent out a replacement that works without issue. Only other issue I had in years of owning this was not being able to find replacement paper discs for the mechanical leak sensor (water makes the paper discs swell which pushes on a valve to close the flow of water), and because I get condensation under my sink I have to replace them more regularly than I'd want to. I contacted iSpring and Francis helped me out with that too. They're very good at after sales support - that's probably the main reason I keep coming back to them, aside from the quality of their product that is. I can easily recommend it to you if you have a 1-stage filter or filter jug and are looking for some real water filtration. The cost of filters is only marginally higher than for a filter jug, and for something that gives you on-demand well filtered water without waiting. ## Features - SUPERIOR PERFORMANCE: The advance 4-stage design, which includes both Ultrafiltration and KDF/GAC stages, removes up to 99% of chlorine and chlorine treatment by-products, lead, arsenic, and much more, while retaining minerals. Noted: This system is NOT a Reverse Osmosis water filtration system and does NOT lower TDS - 4-Stage ULTRA FILTRATION SYSTEM: PP Sediment Filter ((5 microns) removes larger particles like rust, sand, dirt. ) Ultra Filtration Filter (contains hollow fiber membrane technology with a pore size of just 0.01 microns. ) KDF and GAC Filter (provides much better control of particularly problematic contaminants including chloramine, hydrogen sulfide, heavy metals, and other compounds). Fine Activated Carbon Filter (provides final polishing) - SIMPLE AND FLEXIBLE: NO WASTE WATER and No storage water tank required. 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 - FEATURES: Come with premium Chrome finish drinking water faucet. All filters, tubing and other water-contacting parts are manufactured to comply strictly with NSF/ANSI standards for safety and water quality - EASY-TO-INSTALL AND REPLACE FILTER: Push to connect fittings with color-coded tubing simplify the installation process. Filter replacement are designed for ease. No need to disconnect hoses or water lines. Just Twist On / Twist Off filter cartridges make changing filters a snap. Filter life: 6 -12 months, depending on your source water and usage ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B009AEJWZG | | Best Sellers Rank | 235,638 in DIY & Tools ( See Top 100 in DIY & Tools ) 168 in Under-Sink Filters | | Brand | iSpring | | Capacity | 8000 gallons | | Container Type | Faucet | | Country Of Origin | China | | Customer Reviews | 4.3 out of 5 stars 694 Reviews | | EU Spare Part Availability Duration | 12 Months | | Filter Life Cycle | 6 Months | | Global Trade Identification Number | 00662425053063 | | Included Components | Under sink water filter system, parts and tubings, faucet | | Included components | Under sink water filter system, parts and tubings, faucet | | Installation Type | Under Sink | | Item Dimensions L x W x H | 26.7L x 11.4W x 31.8H centimetres | | Item Type Name | 4-Stage High Capacity Premium Under Sink Drinking Water System with 0.1 micron Ultra Filtration membrane | | Item Weight | 2 Kilograms | | LowerTemperature Range | 40 Degrees Fahrenheit | | Manufacturer | iSpring | | Manufacturer Part Number | CU-A4 | | Material | Polyvinyl Chloride | | Material Type | Polyvinyl Chloride | | Model Name | CU-A4 | | Model Number | CU-A4 | | Number of Items | 1 | | Other Special Features of the Product | Tankless | | Power Source | Non electric | | Product dimensions | 26.7L x 11.4W x 31.8H centimetres | | Purification Method | Activated Carbon, Granular Activated Carbon | | Special feature | Tankless | | Supported Water TDS Level Maximum (PPM) | 500 | | UPC | 662425053063 | | Unit Count | 1.0 count | | Upper Temperature Rating | 100 Degrees Fahrenheit | ## Product Details - **Brand:** iSpring - **Capacity:** 8000 gallons - **Included components:** Under sink water filter system, parts and tubings, faucet - **Installation type:** Under Sink - **Material:** Polyvinyl Chloride - **Package information:** Faucet - **Power source:** Non electric - **Product dimensions:** 26.7L x 11.4W x 31.8H centimetres - **Purification method:** Activated Carbon, Granular Activated Carbon - **Special feature:** Tankless ## Images ![CU-A4 0.01 Micron Ultra-Filtration Under Sink Water Filter System | Tankless 4-Stage High Capacity , Remove 99.99% Contaminants, Quick Filter Change with Chrome Faucet, White - Image 1](https://m.media-amazon.com/images/I/712+0L+2SkL.jpg) ## Available Options This product comes in different **Style Name** options. ## Questions & Answers **Q: How many gallons of water will be treated during a filter's lifespan, before they need to be replaced? Also, is there a change indicator?** A: The actual gallon life will vary from customer to customer. As with all replaceable filter cartridges, they have limited space to hold the contaminants they remove from your water. This means that the higher concentration of junk you have in your source water, the faster the filters will run out space to keep filtering and vice versa. The average is about 1100 gallons, but this number may not represent your source water, so individual results could either be more or less than the average. **Q: Has anyone tested the water that comes out of the filter with a TDS meter? I checked mine today and found that the TDS was the same as the tap water** A: Per Josh @ iSpring 3/7/2017 - this will not remove minerals present in your city's tap water, so there should be little difference in total dissolved solids (TDS) count. **Q: Can I connect existing water line(previously connect to refrigerator,tiny size) to this unit or I have use a adaptor? and can I only connect to refrig** A: I answered this before, but after re-reading your question I need to revise my original answer. If you are planning on using this as a primary filtered water supply you will probably find that there is not enough water flow through the original water line that is supplying water to your refrigerator. Maximum flow rate is a function of the diameter of the supply line (among other factors). You could make it work if you had to, but I am thinking the flow rate might be kind of feeble. Why not take the supply from under the sink in the kitchen? **Q: Does this remove flouride?** A: Hi ajb, Unfortunately this unit does not remove fluoride. You will need reverse osmosis in order to remove fluoride. ThanksClaudia ## Customer Reviews ### ⭐⭐⭐⭐⭐ easy to install equipment *by A***S on 20 May 2025* My Experience with the iSpring CU-A4 Under Sink Water Filter I recently installed the iSpring CU-A4 under sink water filter, and I'm genuinely impressed. As someone who's always been a bit skeptical about the true efficacy of home water filtration systems, this unit has completely changed my perspective. First off, the installation was surprisingly straightforward. I'm no plumbing expert, but the clear instructions and well-organized components made the process relatively painless. Within an hour or so, I had fresh, filtered water flowing from my dedicated faucet. And what a difference it makes! The most noticeable improvement is in the taste and smell of the water. Our tap water, while generally safe, often had a slight chlorine odor and a somewhat metallic aftertaste. With the iSpring CU-A4, that's completely gone. The water is crisp, clean, and incredibly refreshing. It's truly a pleasure to drink, and I find myself reaching for water more often throughout the day. Even my coffee and tea taste noticeably better. I also appreciate the compact design of the unit. It fits neatly under my sink without taking up an excessive amount of valuable cabinet space, which is a huge plus in smaller kitchens. The dedicated faucet is sleek and unobtrusive, blending well with my existing fixtures. While I can't scientifically measure the contaminant reduction, the peace of mind knowing that my family is drinking water filtered through a reputable system is invaluable. The four-stage filtration process, including activated carbon and ultrafiltration, gives me confidence that we're significantly reducing chlorine, sediment, and other common impurities. In conclusion, the iSpring CU-A4 under sink water filter is an excellent investment for anyone looking to improve the quality of their drinking water. It's easy to install, produces great-tasting water, and offers genuine peace of mind. Highly recommended! ### ⭐⭐⭐⭐⭐ Worth it - great water and good after sales support even years on *by P***S on 4 February 2025* Long time customer or iSpring. I've installed the american style system in my family homes in Canada and this system in my home in the UK. Their filtered water tastes as it should! I had an issue with the included tap/faucet leaking but iSpring sent out a replacement that works without issue. Only other issue I had in years of owning this was not being able to find replacement paper discs for the mechanical leak sensor (water makes the paper discs swell which pushes on a valve to close the flow of water), and because I get condensation under my sink I have to replace them more regularly than I'd want to. I contacted iSpring and Francis helped me out with that too. They're very good at after sales support - that's probably the main reason I keep coming back to them, aside from the quality of their product that is. I can easily recommend it to you if you have a 1-stage filter or filter jug and are looking for some real water filtration. The cost of filters is only marginally higher than for a filter jug, and for something that gives you on-demand well filtered water without waiting. ### ⭐⭐⭐⭐⭐ Great tasting filtered water, and very good customer support. *by T***D on 19 April 2025* We're really very happy with our new water filter system. It was pretty straightforward to fit, and after running the water through for about 20 - 30 minutes we have water that looks, tastes and smells much better than the regular tap water. You really can tell the difference. No more unpleasant chlorine smell. Having a dedicated tap for the filtered water is a good idea, because then you're not using filtered water to fill up your basin for washing up etc, thus keeping the life in the filters for longer. Fitting the new tap was pretty straight forward on an aluminium kitchen sink. I just drilled a guide hole, and used the tool in the link that I'll put below this review that I bought also from Amazon to cut the hole. Easy to do, just needs a bit of brute force, but it makes a very neat hole. The water from the tap fills a glass at a good speed. One thing to add, is that the customer support is excellent. After fitting, I had a follow up question that I contacted the team about. The reply from Nick was prompt, courteous, and above all really helpful. This should be kept in mind as a big plus point if you're contemplating which manufacturer you should buy from. This is the link to the tool I used to cut the hole in my aluminium sink: https://amzn.eu/d/hEzgCox SagaSave 25mm (16-50MM) Sheet Metal Punch Hole Punch, Metal Inner Hex Hole Cutter for Q.Max, Steel Plate, Stainless Steel ## Frequently Bought Together - iSpring CU-A4 0.01μm Ultra-Filtration Under Sink Water Filter System, Tankless 4-Stage High Capacity, Remove 99.99% Contaminants, Quick Filter Change with Brushed Nickel Faucet, White - iSpring ICEK Ultra Safe Fridge Water Line Connection and Ice Maker Installation Kit for Reverse Osmosis RO Systems & Water Filters, 1/4", 20 feet - iSpring APR40 Pressure Regulator Filter Protection Valve with 1/4" Quick Connect, 40 psi --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.us/products/48256916-cu-a4-0-01-micron-ultra-filtration-under-sink-water](https://www.desertcart.us/products/48256916-cu-a4-0-01-micron-ultra-filtration-under-sink-water) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-08-25*