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Internet # 312549423

Model # K-400H-021-P8

Store SKU # 1005172461

PerforMAX Universal 2 in. High Performance Everything Toilet Tank Repair Kit with Install Tools

$19.82
  • All parts included for a complete Fluidmaster toilet repair kit
  • Easiest installation possible- parts, guide and tools provided
  • Control the tank, bowl and flush water levels and save water
  • View More Details

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Product Details

About This Product

The Fluidmaster K-400H-021 PerforMAX Universal 2 in. High-Performance Everything Toilet Tank Repair Kit offers the most complete solution to repair your toilet fast. Best for use in 1.28 and 1.6 GPF toilets (can use with older 3.5 GPF models). Quickly solve running, noisy or leaky toilet problems with one kit designed to fit every toilet type and provide the simplest install possible. Follow the step-by-step instructions, and use the toilet install tools on the fill valve, flush valve and tank-to-bowl hardware. No bucket, no problem, use the multipurpose package to catch any remaining water and eliminate water mess. This complete toilet repair kit includes the PerforMAX toilet fill valve, a high-performance fill valve featuring 2X greater refill rates than standard models, with ultra-quiet operation and adjustable bowl and tank water settings to customize your water use per flush. The adjustable 2 in. toilet flush valve changes height with a quick 90° turn, no cutting required. Also including the PerforMAX toilet flapper. Chlorine and hard water resistant, it allows you to customize your water use per flush and save water. The universal tank-to-bowl toilet gasket is made to fit any 2 in. flush valve toilet, in a simple two-piece design. This high-performance toilet repair kit is the top solution to repair and upgrade your toilet tank, with all the parts and tools needed for the fastest and easiest installation experience available.

Highlights

  • Fluidmaster's everything kit includes everything you need to fix your toilet in 1 trip and 1 purchase
  • Easy to install, universal design fits 2 in. flush valve toilets
  • Adjustable flush valve eliminates cutting, simply twist to adjust height and fit any 2 in. flush valve
  • Color-coded, helpful install tools included for the fastest installation possible
  • Universal tank-to-bowl gasket for use with all 2-in. flush valve toilets, including KOHLER, Gerber and more
  • Multipurpose package is designed to hold water during install to eliminate mess and hassle
  • PerforMAX 2 in. toilet flapper adjusts to set water use per flush and eliminate water waste
  • Durable stainless steel hardware for a long lifespan
  • Stylish chrome tank lever for a clean finish
  • 7-year warranty
  • Return Policy
  • California residents
     see Prop 65 WARNINGS

Product Information

Internet # 312549423

Model # K-400H-021-P8

Store SKU # 1005172461

Additional Resources

Shop All Fluidmaster

Specifications

Dimensions: H 10 in, W 3.5 in, D 3.5 in

Dimensions

Product Depth (in.)

3.5 in

Product Height (in.)

10 in

Product Width (in.)

3.5 in

Details

Application

Toilet

Color/Finish Family

Assorted Colors

Included

Hardware Included

Material

Plastic

Pack Size

1

Plumbing Part Type

Toilet Kit

Returnable

90-Day

Toilet Repair Kit Type

Complete Toilet Repair Kits

Warranty / Certifications

Manufacturer Warranty

7 years

Questions & Answers

I installed this complete kit last week, and the flapper leaks so much that I need to shut the supply line off after every use of the toilet to keep from wasting water. Why would this happen? I have installed many flappers in the past with no issues
ByNov 19, 2025
2 Answers | 
Answer This Question

I have the same problem!!

By|Dec 2, 2025
    0/0

    Fluidmaster would like the opportunity to learn more and provide help. To get help visit our website Fluidmaster.com where you can find product information and email or chat with a technician. Our toll-free number is 800-631-2011 and we are available 5 days a week Mon-Fri from 5:30 am – 5:00 pm PST.

    By|Nov 19, 2025
      0/0


      Will this fit an American Standard 4049 tank
      ByOct 18, 2025
      1 Answer | 
      Answer This Question

      If you have a 2 piece toilet with a 2 inch flush valve hole at the bottom of the tank then it will fit. The issue may be that you may have to get a specialty flapper aside as this model tank uses a specialty type and using anything other may result in a weak flush to double flushing. We do not offer a flapper replacement for your model. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011.

      By|Oct 21, 2025
        0/0


        Will this fit a mansfield 160?
        ByOct 13, 2025
        1 Answer | 
        Answer This Question

        Yes it will. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011.

        By|Oct 13, 2025
          0/0


          will this work on a sterling 1.6 gal
          BySep 11, 2025
          1 Answer | 
          Answer This Question

          Based on the limited information provided, we are unable to determine whether this kit will work with the specific model under the Sterling brand. More information is required. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011.

          By|Sep 11, 2025
            0/0


            Will this work on an American Standard 4061? Thanks!
            BySep 8, 2025
            1 Answer | 
            Answer This Question

            Yes it will. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011.

            By|Sep 8, 2025
              0/0


              Will this work on a gerber toilet
              ByAug 5, 2025
              1 Answer | 
              Answer This Question

              If you have a 2 piece toilet with a 2 inch lfush valve then this kit should work just fine as it also includes the specialty gasket needed for Gerber toilets. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011.

              By|Aug 5, 2025
                0/0


                Will this fit the Kohler K4436 tank? This tank usually uses a canister mechanism, not a flap valve
                ByJul 14, 2025
                1 Answer | 
                Answer This Question

                If this toilet is using the 3 inch version of the Aquapiston canister flush valve then No you cannot use any replacement for the that as it's proprietary. If it's the 2 inch version then you can. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011.

                By|Jul 14, 2025
                  0/0


                  Will this work on glacier bay toilets?
                  ByJun 11, 2025
                  1 Answer | 
                  Answer This Question

                  Based on the limited information provided we are unable to determine whether this kit will work with your specific model number under the Glacier Brand name. We would need more information to determine if will fit properly. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011.

                  By|Jun 12, 2025
                    0/0


                    Viewing 1-8 of 24

                    Customer Reviews

                    4.5 out of 5

                    • 4.5 out of 355 reviews
                    • 75% recommend this product
                    Filter by:
                    Showing 1-10 of 355 reviews
                    After my husband installed the new fluidmaster fill valve and the new flapper, the toilet started to leak. He then purchased this new fluidmaster set to replace the old flush valve. It continued to leak. He tried for weeks to stop the water leaking. We tested the tank with blue color dye. The flush valve is tight because he reinstalled it 2 times. Maybe the adjustable flush valve tube is leaking? We tried 2 Fluidmaster flappers, one Korky, and the original old flappers. All failed to stop the leaking. Finally, my dad gave me a new flapper he purchased years ago (not sure what brand but it is in black), the leak seems to almost stop to just a very thin line (see attached photo) for a few hours, which could be the residual water inside the toilet bowl rim (at least we want to believe that for now). We wanted to remove the whole thing and buy another brand but just too exhausted to try again for now. Also, the water tank starts having very small bubbles (see photo attached) after every flush, which do not happen to the 3 other toilets in our house. We are not sure if the bubbles are the results of some kind of leak. I wanted my money back for all the problems this bad product caused us.
                    by
                    Response from FluidmasterSupportDec 11, 2025
                    Fluidmaster would like the opportunity to learn more and provide help. To get help visit our website Fluidmaster.com where you can find product information and email or chat with a technician. Our toll-free number is 800-631-2011 and we are available 5 days a week Mon-Fri from 5:30 am – 5:00 pm PST. FluidMaster
                    • Verified Purchase
                    Would have been 5 stars, but
                    Purchased and installed today. The concept is exceptional (i.e. replacement parts and tools). However my kit had a defective fill valve. Replaced all other components but had to resort to using the existing fill valve since the new one had a foreign plastic piece lodged in the bottom that preventing water from flowing from the water supply line. A partial refund is warranted.
                    by
                    Response from FluidmasterSupportJul 7, 2025
                    Fluidmaster would like the opportunity to learn more and provide help. To get help visit our website Fluidmaster.com where you can find product information and email or chat with a technician. Our toll-free number is 800-631-2011 and we are available 5 days a week Mon-Fri from 5:30 am – 5:00 pm PST. FluidMaster
                      • Recommended
                      Great option to rebuild you toilet tank take about 30 minutes to clean it and install full kit I a professional Handyman I install over 200 and no complaints from customers
                      by
                      • Verified Purchase
                      Worked with my Kohler toilet
                      Overall, I found this kit to work well with my older Kohler toilet (which is at least 15 years old). It took me 2.5 hours to uninstall the old parts and then install the new parts. I think the trickiest part was bending the lever arm. The video makes it look easy (taking about 1-2 seconds), but I found it much more difficult to bend. Nevertheless, after patiently applying a strong force to bend the lever arm, I got it to fit nicely into my tank.
                      by
                        • Recommended
                        Flapper is allowing a small leak
                        Like others have experienced, the flapper that came with the repair kit was not sealing all the way on the flush valve. Nevertheless, I proceeded to repair my toilet last night. This morning, I noticed that the water level in my water tank has gone. I made sure there were no leaks coming from anywhere outside the tank, so at this point - It's the flapper that is allowing water to leak from the inside. I followed all the instructions that came with the repair kit and even watched the tutorial video to make sure I did everything correctly. I don't know what to do at this point, unfortunately. I can't return the entire kit without having to disassemble the entire repair kit from my tank...
                        by
                        Response from FluidmasterSupportFeb 1, 2024
                        If you are saying that there is not water left at the bottom of the tank or the water level is below the flapper then the flapper isn't the issue. Water is leaking around the flush valve and not through it as the flapper covers the hole. This means your flush valve or tube in the middle of your tank needs to be replaced as the spud gasket at the bottom of the tank that's located even lower than the flapper is leaking water through. If the water level has stopped right where the flapper covers the hole then the issue is at that location. Ensure that the seat is clear of any debris or gunk development and that the seat is nice and smooth. In some cases product will sit longer than normal and the flapper can dry up. Soak in hot tap water for a couple minutes to help soften up and reinstall. For additional information or help with your product contact Fluidmaster’s Technical Service Department as we are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Chat www.fluidmaster.com/support E-Mail techsupport@fluidmaster.com and Toll Free 800-631-2011. FluidMaster
                          5 found this review helpful
                          the lever just broke before i can install
                          The instruction says to bend the lever arm to fit the side. When i did it, the arm just broke. I did not bend quickly or back and forth repeatedly.
                          by
                          Response from FluidmasterSupportSep 25, 2023
                          Fluidmaster would like the opportunity to help, please contact Fluidmaster’s Technical Service Department for help with your product. We are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Fluidmaster.com/support to Chat, Email or call Toll Free 800-631-2011. FluidMaster
                            1 found this review helpful
                            The flapper did not seal to the flush valve, so when I got it all together, it seeps water into t...
                            The flapper did not seal to the flush valve, so when I got it all together, it seeps water into the bowl. Had to go back and buy a competitors flapper just to get it to work. My first review was rejected because Home Depot thought this was a shipping complaint, but I picked up the box at the store. It's due to the way the parts are placed in the box, which caused the flapper to warp. The little tools are nice, tho.
                            by
                            Response from FluidmasterSupportJul 12, 2021
                            Fluidmaster would like the opportunity to help, please contact Fluidmaster’s Technical Service Department for help with your product. We are available Monday through Friday from 5:30 AM through 5:00 PM Pacific Standard Time. Contact options include: Fluidmaster.com/support to Chat, Email or call Toll Free 800-631-2011. FluidMaster
                              5 found this review helpful
                              Flapper would not stop leaking
                              I bought this to repair a leaky flapper valve......installed per the instructions. Flapper valve was leaking. Disassembled to verify everything, still leaking. Called fluidmaster customer service Who advised me to tighten the flapper valve more than the instructions called for. Disassembled again tightened....still leaks. Called customer service again who advised it must me a bad flapper....They will mail me one in a few days...lol with a teen daughter that isn’t happening. Returning it and buying a different brand.
                              by
                              Response from FluidmasterSupportMar 3, 2021
                              Fluidmaster would like to help, here are a few tips that may solve your problem. When your new flapper is not sealing the drain and the leak is still occurring check to ensure your fill valve refill tube is not inserted or shoved directly into the overflow pipe. If the tubing is inside the overflow pipe you may be creating the leak. The solution here is to remove the refill tube and attach it to the overflow pipe so it does not get inserted into the pipe. If the refill tube is not inserted and the ghost flush is occurring then you may need to replace the entire flush valve (the drain that the flapper is attached to) in order to stop the water loss from the tank. Visit our website Fluidmaster.com/support for videos, troubleshooting tips, email, chat with a technician or call toll free 800-631-2011. We are available 5 days a week Mon-Fri from 5:30 am – 5:00 pm PST. FluidMaster
                                5 found this review helpful
                                This customer chose to rate the product and not provide text.
                                by
                                This customer chose to rate the product and not provide text.
                                by
                                • Verified Purchase
                                Showing 1-10 of 355 reviews

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                                Product Snapshot

                                Ideal for DIYers and pros seeking a complete, high-performance toilet repair solution with easy installation and a 7-year warranty.
                                Great for homeowners looking for a dual-flush conversion, making water conservation easier and more efficient.
                                Perfect for upgrading your toilet with a stylish, all-inclusive kit featuring a cross handle angle stop and braided supply line.
                                Perfect for upgrading your toilet with a stylish and complete brass supply kit, ensuring easy installation and a polished look.

                                Water-saving technology

                                Universal fit

                                Dual flush capability

                                Noise-reduction

                                Material Quality

                                Durable stainless steel hardware
                                Plastic
                                Brass
                                Brass