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Internet #304046627

Model #K-77686-NA

Store SO SKU #1002920229

Aquifer Under-Sink Double Cartridge Water Filtration System

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  • Easy to install under the sink water filtration system
  • Includes cartridge, supply lines, and mounting bracket
  • Reduces chlorine, lead, asbestos, cyst, mercury, pharms and more
  • View More Details

Product Overview

Filter Type
Fitting Size
Top Contaminants Filtered
Number of Filters
Twist and Lock Design
Enjoy greater peace of mind about the water you drink at home. The Aquifer double-cartridge water filtration system effectively reduces contaminants including lead, mercury, chlorine, and pharmaceuticals in your cold water -- without compromising your faucet's performance. While many other systems use coal-based media filters, the Aquifer filter uses ground-up coconut shells, making it more eco-friendly. Under-sink installation is fast and easy, and the compact Aquifer system fits alongside garbage disposals and household items stored below the sink.
  • 2-stage water filtration and absorption system
  • For use with any kitchen, bathroom, or beverage faucet
  • Recommended for use with the wellspring beverage and carafe kitchen faucets
  • Double cartridge system retains your faucet's water flow rate with no performance drop-off
  • Eco-friendly coconut shell based carbon filter
  • Reduces chlorine taste and odor, chloramine, particulate class I, lead, asbestos, cyst, mercury, turbidity and select pharmaceuticals, see performance data sheet for individual contaminants and reduction performance
  • Includes K-77688 aquifer 2-pack replacement cartridge
  • Filter head automatically turns off the water supply when cartridge is removed
  • 1.70 GPM (gallons per minute) maximum flow rate at 60 PSI
  • Postage-paid recycling program for used cartridges to reduce solid waste to landfills
  • High-impact plastic construction
  • Under-sink installation
  • Quarter-turn twist cartridge for easy installation and replacement
  • For cold water use only

Info & Guides

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NameUnder Sink Dual Flow Water Filtration SystemAquifer Under-Sink Double Cartridge Water Filtration SystemRedi-Twist Purifier 3-Stage Drinking Water Filtration SystemAqua-Pure Under Sink Dedicated Faucet Water Filtration System AP-DWS1000 (1 Per Case)
Contaminants FilteredLead, ChlorineLead, Chlorine, Bacteria, Copper, Fluoride, IronLead, Chlorine, BacteriaLead, Chlorine
House Hold SizeUnspecified3-4 people5-6 people5-6 people
IncludesHardware,Installation kitFilterFaucet,Hardware,Installation kitFaucet,Hardware,Installation kit
Number of Stages2 Stage1 Stage3 Stage3 Stage
Filtration MethodCarbon BlockCoconut Shell CarbonHollow Fiber MembraneCarbon Block
Ease of InstallDrilling RequiredEasy InstallDrilling RequiredDrilling Required
FeaturesNo additional featuresTwist and lock designAutomatic shutoffAutomatic shutoff
Replacement Filter TypeUnder Sink Replacement FiltersUnder Sink Replacement FiltersUnder Sink Replacement FiltersUnder Sink Replacement Filters
Number of filters included2232
View ProductView ProductView ProductView Product



Fitting size (in.)
Product Depth (in.)
3.375 in
Product Height (in.)
12.0625 in
Product Width (in.)
7 in


Application Type
Bacteria Reduction (%)
Chlorine reduction (%)
Not Applicable
Contaminants Filtered
Lead, Chlorine, Bacteria, Copper, Fluoride, Iron
Copper Reduction (%)
Ease of Install
Easy Install
Twist and lock design
Filtration Method
Coconut Shell Carbon
Fitting style
Fluoride Reduction (%)
House Hold Size
3-4 people
Iron Reduction (%)
Lead reduction (%)
Maximum feed water pressure (psi)
Maximum feed water temperature (F)
Maximum filtered water flow (gallons per min.)
Minimum feed water pressure (psi)
Minimum feed water temperature (F)
Number of filters included
Number of Stages
1 Stage
Pack Size
Product Weight (lb.)
5.410 lb
Replacement Filter Type
Under Sink Replacement Filters
Water Filtration System Type
Under Sink

Warranty / Certifications

Certifications and Listings
CSA Certified,NSF Certified
Manufacturer Warranty
One-Year Limited Warranty

Questions & Answers

Typical questions asked about products:

  • Is the product durable?
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Customer Reviews

  • 4.6
    out of 29 reviews
  • 86% recommend this product
Filter by:
Showing 1-10 of 29 reviews
Water pipe connection leaks
After I connected the water pipe for the first time, the water leaked seriously, and the water was still leaking after unplugging the connector part and connecting again. I don’t know why it didn’t work properly. After connecting it three times, it can work normally without water leakage, but I am worried that there will be water leakage in the future.
Response from Kohler Product ExpertJan 13, 2021
Hi Gary, thank you for contacting Kohler Co. I'm very sorry to hear your Aquifer water filter was difficult to install. The leaking could have been prompted by a misalignment on the valve head. First, we recommend reinstalling your previous cartridge. Next, rotate the old cartridge as far to the left as possible, until it stops. Once you have done this, you will be aligning the valve head to be prepared for the new cartridge. You can then reinstall the new K-77686-NA Aquifer. Please email us at KohlerCustServ@kohler.com with any question or for additional assistance. We're here to help. -Sarah S. Kohler Customer Service
    Nice clean water
    [This review was collected as part of a promotion.] This is a great system for the kitchen. It's pretty compact so doesnt take up a ton of room. We installed it in our kitchen sink. Theres also a garbage disposal and instant hot water but still plenty of room for this. Installation is fairly straightforward but you will have to have basic plumbing knowledge to install this. I like that I can now have clean filtered water from the faucet instead of having to get it from the fridge. The water from this filter tastes really clean with no hint of minerals. I feel better about drinking from the tap knowing that I am drinking clean and filtered water. This is a high quality product and I am very happy with everything.
      • Recommended
      Crisp water
      Easy installation. Crisp filtered water. Tastes significantly removed from tap
      • Verified Purchase
        No good after 2month water dripping very slow...
        No good after 2month water dripping very slow
        Response from Kohler Product ExpertSep 23, 2021
        Hi HomeDepotCustomer, this is Sarah with Kohler Co. I'm very sorry to hear your Aquifer filtration cartridge is producing a low flow after 2 months. We'd like to connect with you directly to help find a solution. Please email us at KohlerCustServ@kohler.com. Sincerely, Sarah S. Kohler Customer Service
          Water tastes good but...
          Switched from Brita long-lasting filter system and the water tastes as good as (if not better). However, after a few days of use, water-flow has gotten so much slower (50-75% less) that it now takes more than 1 min to fill 64oz bottle...
            System works great… no loss of water pressure....
            System works great… no loss of water pressure.
                Easy to install , works great!...
                Easy to install , works great!
                  So easy to install. the water tastes great. One of...
                  So easy to install. the water tastes great. One of the best buys i have made.
                  • Verified Purchase
                  Showing 1-10 of 29 reviews