--- product_id: 11324872 title: "iSpring CU-A4 4-Stage Ultra Filtration Under Sink Water Filter System" brand: "ispring" price: "$380.43" currency: USD in_stock: true reviews_count: 13 category: "I Spring" url: https://www.desertcart.us/products/11324872-ispring-cu-a4-4-stage-ultra-filtration-under-sink-water store_origin: US region: United States of America --- # 0.01μm ultrafiltration membrane Tankless, no wastewater 4-stage filtration system iSpring CU-A4 4-Stage Ultra Filtration Under Sink Water Filter System **Brand:** ispring **Price:** $380.43 **Availability:** ✅ In Stock ## Summary > 🚰 Elevate your tap game with ultra-pure water—because your health deserves the best! ## Quick Answers - **What is this?** iSpring CU-A4 4-Stage Ultra Filtration Under Sink Water Filter System by ispring - **How much does it cost?** $380.43 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/11324872-ispring-cu-a4-4-stage-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 - • **Effortless Maintenance:** Twist On/Twist Off filter cartridges with push-to-connect fittings make replacements a breeze. - • **Sleek & Durable Design:** Premium brushed nickel faucet and NSF/ANSI certified materials blend style with safety. - • **Crystal-Clear Hydration:** Removes 99.99% contaminants including chlorine, lead & arsenic without stripping essential minerals. - • **Next-Level Filtration Tech:** Advanced 4-stage system with hollow fiber membrane and KDF/GAC filters for superior water purity. - • **Space-Smart & Eco-Friendly:** Tankless design eliminates wastewater and bulky storage tanks—perfect for modern kitchens. ## Overview The iSpring CU-A4 is a high-capacity, tankless under-sink water filtration system featuring a cutting-edge 0.01μm ultrafiltration membrane and a 4-stage filtration process. It removes 99.99% of contaminants like chlorine, lead, and arsenic while retaining beneficial minerals. Designed for easy installation and maintenance, it includes a stylish brushed nickel faucet and complies with NSF/ANSI safety standards, delivering clean, great-tasting water without wastewater or bulky tanks. ## Description 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 | 0.01μm, Space-saving, Reduces 99.99% Contaminants, Quick Filter Change, With Brushed Nickel Faucet, Up to 12 Months - Undersink Water Filtration Systems - desertcart.com Review: High Quality Tank - Very easy to install and it's an easy replacement for the tank that wore out. Once installed, water pressure is very high, and we now have a strong stream running from the faucet. Also went through the easy process to register the tank for the warranty. No issues and I was guided through the process by a representative named Robert. iSpring products are great and I highly recommend them. Review: Great quality and easy installation - I bought the iSpring T32M to increase my RO system's capacity and pressure. The initial bladder pressure was perfect at 7.5 psi. Works great and excellent water flow! Great customer service from Robert at iSpring too. ## 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, and much more, while retaining minerals. Noted: This system is NOT a Reverse Osmosis water filtration system and does NOT lower TDS. - 4-Stage ULTRAFILTRATION SYSTEM: PP Sediment Filter (5 microns) removes larger particles like rust, sand, dirt. Ultrafiltration membrane 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 brushed nickel 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 for simplify setup. 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 | #4,064 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #11 in Under-Sink & Countertop Filtration | | Brand | iSpring | | Brand Name | iSpring | | Capacity | 8000 gallons | | Container Type | Faucet | | Customer Reviews | 4.6 out of 5 stars 7,166 Reviews | | Filter Life Cycle | 6 months | | Global Trade Identification Number | 00662425053063 | | Included Components | Under sink water filter system, parts and tubings, faucet | | Installation Type | Under Sink | | Item Dimensions L x W x H | 10.63"L x 4.33"W x 12.6"H | | Item Type Name | 4-Stage High Capacity Premium Under Sink Drinking Water System with 0.1 micron Ultra Filtration membrane | | Item Weight | 2 kg | | LowerTemperature Range | 40 °F | | Manufacturer | iSpring | | Material | 0.01μm Ultra-Filtration, Lead-free & BPA-free Material, Leak-Free, Space-Saving & Easy to Install Material 0.01μm Ultra-Filtration, Lead-free & BPA-free Material, Leak-Free, Space-Saving & Easy to Install See more | | Material Type | 0.01μm Ultra-Filtration, Lead-free & BPA-free Material, Leak-Free, Space-Saving & Easy to Install | | Model Name | CU-A4 | | Model Number | CU-A4 | | Number of Items | 1 | | Other Special Features of the Product | 4-Stage 0.01 micron ultra-filtration, Heavy Duty, Leak Proof, Reduces chlorine, lead, arsenic, odor, metal and more | | Part Number | CU-A4 | | Power Source | No Need | | Product Dimensions | 10.63"L x 4.33"W x 12.6"H | | Purification Method | Mechanical Filtration, Chemical Absorption, Redox, and Ultrafiltration | | Special Feature | 4-Stage 0.01 micron ultra-filtration, Heavy Duty, Leak Proof, Reduces chlorine, lead, arsenic, odor, metal and more Special Feature 4-Stage 0.01 micron ultra-filtration, Heavy Duty, Leak Proof, Reduces chlorine, lead, arsenic, odor, metal and more See more | | UPC | 662425053063 | | Unit Count | 1 Count | | Upper Temperature Rating | 100 °F | | Warranty Description | 30-Day money-back guarantee. 1-Year Manufacturer Warranty. Lifetime support from Atlanta, GA. | ## Product Details - **Brand:** iSpring - **Capacity:** 8000 gallons - **Included Components:** Under sink water filter system, parts and tubings, faucet - **Installation Type:** Under Sink - **Package Information:** Faucet - **Power Source:** No Need - **Product Dimensions:** 10.63"L x 4.33"W x 12.6"H - **Purification Method:** Mechanical Filtration, Chemical Absorption, Redox, and Ultrafiltration ## Images ![iSpring CU-A4 4-Stage Ultra Filtration Under Sink Water Filter System - Image 1](https://m.media-amazon.com/images/I/81zOpUpCr+L.jpg) ## Available Options This product comes in different **Set** 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 ### ⭐⭐⭐⭐⭐ High Quality Tank *by C***Z on July 14, 2026* Very easy to install and it's an easy replacement for the tank that wore out. Once installed, water pressure is very high, and we now have a strong stream running from the faucet. Also went through the easy process to register the tank for the warranty. No issues and I was guided through the process by a representative named Robert. iSpring products are great and I highly recommend them. ### ⭐⭐⭐⭐⭐ Great quality and easy installation *by J***2 on July 20, 2026* I bought the iSpring T32M to increase my RO system's capacity and pressure. The initial bladder pressure was perfect at 7.5 psi. Works great and excellent water flow! Great customer service from Robert at iSpring too. ### ⭐⭐⭐⭐⭐ We originally had a RO system that provided us with excellent tasting water *by S***E on September 23, 2015* I am a General Contractor/Home builder. We originally had a RO system that provided us with excellent tasting water, but took up most of the under-cabinet and had to be sanitized with bleach at each filter change.. We don't have hard water and our tap water is drinkable but we wanted it cleaner, and the RO had intermittent leak problems. Could I find a system that would relieve us of the clutter , the maintenance, the water leaks under the cabinet, and still get great water? I decided to give the CU-A4 a shot. SO, Here goes what I didn't like, and then what I liked: CONS: 1. The directions do NOT adequately describe how to make the water connections. To someone who has installed with these type connections it is an obvious "no-brainer", but to the rest of us......... Parts of the directions appeared to be for a different unit, and especially the section on installing the faucet, which was obviously from their RO system and was not anywhere close to describing the faucet enclosed. The faucet enclosed is an "air gap" style which requires a hole in your sink deck or in your counter of 1 1/8" minimum. The threaded pipe that will go through this opening is 1" in diameter. If your existing hole is anywhere from 1 1/2" to 1 1/8" the provided washer will work fine. 2. While there was plenty of 1/4" tubing to do the installation, There are 3 colors of tube, red, white and blue. They provided plenty of blue and white, but not red, therefore I used white and labeled it red to make the job a clean install. 3. There is no discussion in the manual of run-in time after completing the install. The water was barely drinkable after letting it free-flow for approximately 10 minutes as suggested in the notes . After flushing the system with approximately 15 more gallons the water was crystal clear and the flavor has become progressively better and better and has stabilized. PROS: 1. The system IS actually easy to install when you have familiarized yourself with everything they have sent and how it will work with your existing plumbing and sink. AND you have purchased anything you might need so the system will integrate seamlessly. 2. The snap-fit connections work great and do not leak a drop. 3. Twist on replacement filters. How could it get any simpler??? 4. Takes up minimal space. 5. The faucet is all metal construction. 6. After initial flushing and after the first week of use (approx. 1 Gal per day)t the water tastes GREAT. As good or better than any of the bottled waters we have tested against. 7. Every time I have called them (of course during business hours...duh...) they have been very responsive. So, customer service gets a nod. CONCLUSION: Well worth the money, Simple design and install Great tasting water NOTES: 1.There is a review about salt taste. If you have softened water, then you may want to contact your service company regarding what is best to work with your existing system. At the very least do an internet search on how softeners and filters can work together before purchasing this system. 2. There are reviews that mention a 1/2" 3-way valve and having to buy adapter fittings. My system came with a 3/8 to 3/8" 3-way valve (which worked perfectly), so it seems iSpring has changed it to the more typical size. 3. One reviewer gave 3 stars because this system does not reduce TDS and it cost them 10% restocking to return it. TDS is reduced by RO systems, This is NOT a RO system. iSpring does not claim reduced TDS. If you need reduced TDS...iSpring has a very highly rated RO system ( http://www.amazon.com/iSpring-RCC7-Reverse-featuring-See-through/dp/B003XELTTG/ref=cm_cr_pr_product_sims?ie=UTF8 ) for about $200.00. 4. Most every review says the directions suck. I can attest to that. They do! Layout everything from the box, familiarize yourself with it, identify any problems with your existing plumbing. Take the 3-way valve with you to your local home improvement store and buy whatever you need. 5. Make certain you have the correct tools to accomplish the install. 6. For a water tight connection fit, remove the blue "horseshoe" clips and FIRMLY push the 1/4" tubing approximately 5/16" in to the couplers until you feel it "bottom out", check the assembly by firmly pulling on the 1/4" tubing. Replace the blue clip. 7. I made all of my tubing the same length and long enough for me to remove the filter manifold a couple feet from the cabinet to facilitate changing the filters when that time comes. The tubing is coiled and taped up (love that blue tape), and will be easy to undo and stretch out. 8. I purchased an extra set of filters ahead of time, and store them right next to the unit. 9. Instead of changing my filters by use of a calendar (such as recommended by the manufacturer, every 6 months), I will change them based on usage. Since we only use it for drinking and cooking, we likely will never hit a max avg of 3gals per day. Most filter manufacturers claim 6mos. is relatively equal to 1200 Gals. Therefore 3 gals x 365 days = 1095 gals. (1095 is approx 90% of 1200 filter life). That is when I will change mine, at about 1 year. You also can adjust your schedule based on this formula. If you use 6 1/2 gals per day, you will hit the 1200 threshold at about 6 months. Were you to use 10 gals per day you would want to replace the filters after 4 months. AND so on. If you don't have a basin wrench, get one from your tool store, (see images) Make your life easier. ## 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/11324872-ispring-cu-a4-4-stage-ultra-filtration-under-sink-water](https://www.desertcart.us/products/11324872-ispring-cu-a4-4-stage-ultra-filtration-under-sink-water) --- *Product available on Desertcart United States of America* *Store origin: US* *Last updated: 2026-08-20*