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iSpring FG15B-KS Premium Quality Super Capacity GAC and KDF Carbon Filter Replacement Cartridge for Direct Connect Under Sink Water Filtration System US21B & US21B-CPB, 10” x 4.5”

iSpring FG15B-KS Premium Quality Super Capacity GAC and KDF Carbon Filter Replacement Cartridge for Direct Connect Under Sink Water Filtration System US21B & US21B-CPB, 10” x 4.5”

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Regular price $74.46
Regular price Sale price $74.46
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  • 24/7 Customer Support
  • Risk-Free 30-Day Returns
  • Fast & Reliable U.S. Shipping

30-Day Hassle-Free Returns

Not satisfied? Return your order within 30 days for a full refund or exchange — simple and easy.

✔ Easy return process

✔ Fast refunds

✔ No hidden conditions

Fast U.S. Shipping

We ship within the United States only — no international delays.

✔ Processing time: 1–2 business days

✔ Delivery time: 3–7 business days

✔ Real-time tracking available

👉 Track your order anytime from the header via Track Order

About This

  • [Superb Filtration Performance] FG15B-KS 10” x 4.5” compound filter is designed to effectively remove chlorine, lead, mercury, hydrogen sulfide, iron, chloride, chloramines, herbicides, odors, and other contaminants or impurities.
  • [Water Health Warrior] Teaming up with carbon filters like iSpring FC15B, this filter is super powerful to remove the unpleasant taste or odor left in chlorinated water while maintaining the protection benefits of chlorine in water disinfection. They also tackle problems like turbidity, cloudiness, colors, bad taste, and odors like hydrogen sulfide that smells like rotten eggs. A reliable shield that protects you and your family from ingesting harmful chemicals or contaminants in your tap water.
  • [Great Compatibility] Official 1st stage replacement filter cartridge for iSpring direct connect Point-of-Use(POU) undersink water filtration system US21B. Fits standard 10" undercounter or whole house water filtration systems. Individually sealed for freshness.
  • [Exceptional Filter Life] Based on the contaminant levels in source water and your water use, we suggest that you change your filters every 8-12 months for best filtration performance. Hassle-free filter cartridge replacement is a breeze!
  • [TDS Note] Please be noted that the system for which this filter works is NOT designed to reduce Total Dissolved Solids(TDS) removal and instead keeps essential minerals in your water. If you are interested in a filter that significantly reduces TDS, please consider our iSpring Reverse Osmosis (RO) systems RCC7 series or tankless RO500.
  • [Peace-of-Mind Support] We offer tech and CS support via phone and email from Atlanta, GA. Contact our responsive and professional team for product selection to suit your water filtration needs and after-sale support to maximize your user experience. Now, and years to come, we will be right here and ready to help.
  • Capacity: 80000 gallons

Overview

  • Material : KDF+GAC
  • Product Dimensions : 4.5"D x 4.5"W x 10"H
  • External Testing Certification : NSF
  • Product Benefits : Provides superb filtration performance, removing various contaminants and impurities for clean and safe drinking water Provides superb filtration performance, removing various contaminants and impurities for clean and safe drinking water
  • Brand : iSpring
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Is Hard Water or Contaminated WaterDamaging Your Home?
Signs You May Be Experiencing Problems With Your Tap Water
Protect Your Home Appliances
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Softer Skin & Healthier Hair
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Pure, Better-Tasting Drinking Water
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Prevent Costly Hard Water Damage
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Reduce Limescale Buildup
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Clean Water, Whole Home
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Protect Your Home Appliances
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Softer Skin & Healthier Hair
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Pure, Better-Tasting Drinking Water
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Prevent Costly Hard Water Damage
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Reduce Limescale Buildup
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Clean Water, Whole Home
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RO Water Filters Reverse Osmosis Water Filters for Pure Drinking Water
Salt Water Softeners Salt Water Softeners for Powerful Hard Water Treatment
Pure Water. Better Living.

Experience the difference clean, softened water makes in your daily life — from healthier skin to better tasting drinking water.

👉 Softer skin and smoother hair with every shower.

Descaling Solutions Descaling Solutions for Removing Limescale and Mineral Buildup
👉 Enjoy healthier skin and hair with every use.
Water Filter Cleaning Kits

👉 Prevent scale buildup and keep your appliances running efficiently.

Under Sink Water Filters

👉 Softer, brighter clothes that last longer with every wash.

Reverse Osmosis Systems Best Reverse Osmosis Systems for Clean Drinking Water

See the Difference in Your Water — Instantly

Hard water, chlorine, and hidden contaminants can affect your health, skin, and appliances.

Our advanced filtration system removes impurities and delivers clean, safe water throughout your entire home.

Feel the difference in every drop — from your kitchen to your shower.

Impurity Reduction 95%
Chlorine Removal 99%

FAQ

Is installation difficult?
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No. Our systems are designed for easy DIY installation and most homeowners can install them without professional tools. If you need help, our support team is always available.
Do I need a plumber to install the system?
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No plumber is required. The system connects directly to your existing plumbing with simple fittings.
How does this system improve water quality?
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Our filtration system helps reduce common impurities and minerals that cause hard water problems, improving the taste and clarity of your water.
Will this help protect my appliances?
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Yes. Hard water minerals can build up inside appliances. Our system helps reduce scale buildup, helping extend the life of washing machines, dishwashers, and water heaters.
How often do filters need to be replaced?
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Most filters only need replacement every 6–12 months, depending on usage and local water conditions.
Will this improve my skin and hair?
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Many customers notice softer skin and smoother hair after switching to filtered or softened water.
What if I'm not satisfied with the system?
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If you're not completely satisfied, you can return your product within 30 days for a full refund.
Easy to install — no plumber required. Our experts are here if you need help.
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