Name: iSpring CU-A4
Brand: iSpring
SKU: B009AEJWZG
Price: 158.99 USD
Availability: InStock
Rating: 4.6 (6736 reviews)

Expert Review Analysis

The iSpring CU-A4 is a tankless, 4-stage ultrafiltration system designed for under-sink installation that removes up to 99% of 700 contaminants, including lead, chlorine, and PFAS, while retaining beneficial minerals. Unlike reverse osmosis systems, it produces no wastewater and requires no storage tank, making it a space-efficient solution for clean drinking water.

✓ Best for: Homeowners seeking improved drinking water taste and safety without the complexity of reverse osmosis. Apartment dwellers and RV owners with limited under-sink space who need a compact filtration solution. Users prioritizing mineral retention in their filtered water rather than complete demineralization. Households wanting chemical-free filtration without the environmental concern of wastewater generation. Coffee enthusiasts and those requiring filtration for refrigerator or coffee maker applications✗ Not ideal for: Users requiring reduction of Total Dissolved Solids (TDS) as this system does not lower TDS levels. Consumers seeking a filtration system with verified independent third-party performance testing data. Households looking for a low-maintenance solution with infrequent filter replacement cycles

Pros

✓Removes up to 99% of 700 contaminants including lead, chlorine, PFAS, arsenic, and heavy metals
✓

Best Seller Rank History

Now#21Best#2Worst#890 +128

Lower = better sales rank

Specifications

Design

Height13.00 inches mm

Width4.00 inches mm

Length15.00 inches mm

Weight6.00 LB g

Features

Faucet FinishBrushed Nickel

Storage Tank RequiredNo

Filter Replacement MethodTwist On / Twist Off

Connection TypePush-to-connect fittings

TDS ReductionNo

General

BrandiSpring

ModelCU-A4

ColorWhite

Warranty1-Year Manufacturer Warranty

Installation TypeUnder Sink

Performance

Contaminant Removal Rate99% to 99.99%

Number of Contaminants Removed700

Filter Lifespan6-12 months

Sediment Filter Rating5 microns nm

Membrane Pore Size0.01 microns nm

Filtration Technology

Membrane Type0.01-micron hollow fiber ultrafiltration

Filtration Stages

Stage 15-micron PP Sediment Filter

Stage 3KDF and Activated Granular Carbon (GAC) Filter

Stage 4Fine Activated Carbon Filter

Certification

Standards ComplianceNSF/ANSI standards for all water-contacting components

Dimensions & Weight

Height12.5 inches

Width4.5 inches

Depth10.5 inches

Weight4.40924524 pounds

Research Sources

ispringfilter.com

ispringwatersystems.com

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iSpring CU-A4

Expert Review Analysis

Best Seller Rank History

Specifications

Design

Features

General

Performance

Filtration Technology

Filtration Stages

Certification

Dimensions & Weight

Research Sources

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