---
product_id: 76258357
title: "550DFRK-3 DuoFlush Complete Fill and Dual Flush Conversion System, 2"
brand: "fluidmaster"
price: "€ 112.01"
currency: EUR
in_stock: true
reviews_count: 10
category: "Fluidmaster"
url: https://www.desertcart.be/products/76258357-550dfrk-3-duoflush-complete-fill-and-dual-flush-conversion-system
store_origin: BE
region: Belgium
---

# Up to 45% water savings 2x faster refill rate Fits any 2” flush valve toilet 550DFRK-3 DuoFlush Complete Fill and Dual Flush Conversion System, 2

**Brand:** fluidmaster
**Price:** € 112.01
**Availability:** ✅ In Stock

## Summary

> 💧 Upgrade your flush, save the planet, and your wallet!

## Quick Answers

- **What is this?** 550DFRK-3 DuoFlush Complete Fill and Dual Flush Conversion System, 2 by fluidmaster
- **How much does it cost?** € 112.01 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.be](https://www.desertcart.be/products/76258357-550dfrk-3-duoflush-complete-fill-and-dual-flush-conversion-system)

## Best For

- fluidmaster enthusiasts

## Why This Product

- Trusted fluidmaster brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Durable & Reliable:** Long-lasting silicone seal and robust components built to outlast water conditions.
- • **Universal Retrofit:** Seamlessly upgrades any 2-inch flush valve toilet, old or new.
- • **Eco-Smart Dual Flush:** Slash water use by up to 45% without sacrificing performance.
- • **Precision Adjustable:** Customize full and half flush volumes for perfect efficiency.
- • **Rapid Refill Technology:** PerforMAX valve delivers twice the refill speed for quick readiness.

## Overview

The Fluidmaster 550DFRK-3 DuoFlush Conversion System transforms any 2-inch flush valve toilet into a high-efficiency dual flush model, cutting water usage by up to 45%. Featuring the PerforMAX fill valve for twice the refill speed and fully adjustable flush settings, it’s designed for easy installation and long-term durability, making it the smart choice for eco-conscious professionals seeking both savings and performance.

## Description

Product Description The Fluidmaster 550DFRK Duo Flush System gives you a tool to help use less water and save more money. A complete fill and dual flush conversion system. The Dual Flush System retrofits into any 2-Inch flapper toilet and uses up to 45-Percent less water than the original tank parts. Suitable for 1.6 GPF and higher 3.5+ gallons per flush models. The durable silicone seal lasts for years. While the PerforMAX valve regulates water flow and improves overall performance. Adjustable for both full and half flush. Fully adjustable for a wide range of settings without removing the valve. Parts included with Duo Flush Complete System purchase include: Dual Action Handle, PerforMAX Fill Valve, DUO Flush Valve, Refill Clip, Refill Tube, Shank Washer, Fill Valve Locknut, Angled Seat Adapter (optional), Dual Action Handle Locknut, Roller Clamp, and Hose Clamps. From the Manufacturer Fluidmaster the #1 toilet repair brand in the world. Fluidmaster’s complete line of toilet repair parts includes fill valves, flush valves, flappers, tank levers, dual flush valves, bowl wax, toilet repair kits, seals, connectors and more, and are found in more toilets than all other brands. The customer’s first choice and preferred supplier of toilet tank trim since 1957. With manufacturing facilities across the world, Fluidmaster reaches over 90 countries worldwide with unparalleled quality.

Review: Easy to install, durable, more than pays for itself. - Have been using Fluidmaster duo flush for over a decade. The older design the cable would eventually break, but these units would last well past the 5 year warranty. People do not realize that pretty much no toilet components last forever due to water conditions. Most municipal water in the US is chlorinated and is considered hard water. There’s also areas with the opposite such as acidic water. Either way seals and mechanisms wear out. Even the best Korky flapper with 10 year warranty will eventually fail. Anyway I easily get over 5 years out of these units. Usually the mechanical parts break, the plastics. Ok $6 or less a year which pays for itself with water savings. What’s important is to follow the directions and have some clue what you are doing. You need to adjust the fill and 1 and 2 flush volumes which will vary by toilet. Once you are dialed in, you will notice the savings within months. No more full flush for urine. No more over flush, over fill waste. No more replacing failed flappers every few years. Even with good flappers, because of high chlorine in my water flappers would be done by year 3, that’s $10+ dollars every 3 years plus water waste from leaks that probably went on for months. There’s other conversion kits out there, but opinion this is the best. They often make design improvements such as the cable and the flush handle mechanism. You’re lowering your water bill and use and still getting adequate flushing.
Review: Great replacement with a dual flush capability - I bought one of these to replace a leaking valve and love how you can adjust the fill for both the full and half flushes. Great way to save water! It's a bit complicated to install, but the instructions are comprehensive. Also, note that the flush handle threads are reverse, so don't do what I did and break it off trying to remove it. Luckily I contacted Fluidmaster and they sent me a replacement flusher (they don't sell just the handle). I like it so much I'm buying 2 more for my other toilets. Just ensure it's compatible with your current toilet. I have one newer one that it won't fit.

## Features

- Convert your existing 2” flush valve toilet to Dual Flush technology
- Save water & money, uses up to 45% less water
- Retrofits to any 2” flush valve toilet, 1.6 GPF and pre 1994 3.5+ gallon per flush models
- Easy-to-install and fully adjustable for a wide range of settings, without removing the valve
- Complete fill & dual flush conversion system
- Full and half flush, Dual Action toilet flush lever included
- Replace noisy and slow filling inefficient models
- PerforMAX High Performance Fill Valve included for 2x greater refill rate

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B008NHRW76 |
| Best Sellers Rank | #286,696 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #408 in Toilet Flush Valves |
| Brand Name | Fluidmaster |
| Connector Type | Barb |
| Customer Reviews | 4.2 4.2 out of 5 stars (606) |
| Exterior Finish | Chrome,Plastic |
| Included Components | Rough Plumbing;Parts and Repair;toilet-repair-kits |
| Inlet Connection Size | 2 Inches |
| Inlet Connection Type | Barb |
| Item Dimensions | 4.3 x 8.1 x 12.4 inches |
| Item Type Name | Flush Valve Duo Flush Kit |
| Item Weight | 1.9 Pounds |
| Manufacturer | Fluidmaster |
| Manufacturer Part Number | 550DFRK-3 |
| Manufacturer Warranty Description | Warranty |
| Material Type | Plastic |
| Model Number | 550DFRK-3 |
| Number of Pieces | 2 |
| Number of Ports | 2 |
| Outlet Connection Size | 2 Inches |
| Outlet Connection Type | Barb |
| Set Name | Fluidmaster 550DFRK-3 DuoFlush Complete Fill and Dual Flush Conversion System |
| Size | 2 |
| Specification Met | ADA, WaterSense |
| Thread Size | 2 inches |
| Thread Type | No Thread |
| UPC | 039961010100 |
| Unit Count | 1.0 Count |
| Valve Type | flush valve |

## Product Details

- **Brand:** Fluidmaster
- **Exterior Finish:** Chrome,Plastic
- **Inlet Connection Size:** 2 Inches
- **Inlet Connection Type:** Barb
- **Item dimensions L x W x H:** 4.3 x 8.1 x 12.4 inches
- **Material:** Plastic
- **Number of Ports:** 2
- **Outlet Connection Size:** 2 Inches
- **Outlet Connection Type:** Barb
- **Specification Met:** ADA, WaterSense

## Images

![550DFRK-3 DuoFlush Complete Fill and Dual Flush Conversion System, 2 - Image 1](https://m.media-amazon.com/images/I/51D5wbbf+8L.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Easy to install, durable, more than pays for itself.
*by S***M on February 18, 2025*

Have been using Fluidmaster duo flush for over a decade. The older design the cable would eventually break, but these units would last well past the 5 year warranty. People do not realize that pretty much no toilet components last forever due to water conditions. Most municipal water in the US is chlorinated and is considered hard water. There’s also areas with the opposite such as acidic water. Either way seals and mechanisms wear out. Even the best Korky flapper with 10 year warranty will eventually fail. Anyway I easily get over 5 years out of these units. Usually the mechanical parts break, the plastics. Ok $6 or less a year which pays for itself with water savings. What’s important is to follow the directions and have some clue what you are doing. You need to adjust the fill and 1 and 2 flush volumes which will vary by toilet. Once you are dialed in, you will notice the savings within months. No more full flush for urine. No more over flush, over fill waste. No more replacing failed flappers every few years. Even with good flappers, because of high chlorine in my water flappers would be done by year 3, that’s $10+ dollars every 3 years plus water waste from leaks that probably went on for months. There’s other conversion kits out there, but opinion this is the best. They often make design improvements such as the cable and the flush handle mechanism. You’re lowering your water bill and use and still getting adequate flushing.

### ⭐⭐⭐⭐⭐ Great replacement with a dual flush capability
*by J***M on December 9, 2025*

I bought one of these to replace a leaking valve and love how you can adjust the fill for both the full and half flushes. Great way to save water! It's a bit complicated to install, but the instructions are comprehensive. Also, note that the flush handle threads are reverse, so don't do what I did and break it off trying to remove it. Luckily I contacted Fluidmaster and they sent me a replacement flusher (they don't sell just the handle). I like it so much I'm buying 2 more for my other toilets. Just ensure it's compatible with your current toilet. I have one newer one that it won't fit.

### ⭐⭐⭐⭐ It depends on your toilet's flush performance
*by B***S on April 30, 2015*

Installation was a breeze. I spent 10 minutes skimming over the instructions, and probably 30 minutes for installation and adjustment. Adjustment takes the longest amount of time, because you have to keep flushing the toilet and waiting for it to refill before testing the next adjustment. I don't understand why some reviewers said that it took them so long to read the instructions and install the unit. I have lots of experience with replacing toilet fill valves and such, so maybe it was easier for me than it was for some people. As one reviewer mentioned, you have to make sure that you get the most current version of this product. I chose the lowest priced option with free Prime shipping, and the product came from the seller named "Innovative Retail Market". I received the old version of the product from this seller, so I cannot recommend them. Fluid Master happily replaced it with the newer model 550DFRK-1 (the -1 indicates that it is the newer version). I used my water meter to measure how much water my toilet used before I installed this unit. It used 1.9 gallons per flush (gpf). This is slightly more than the rated 1.6gpf printed on the toilet. I suspect that the difference has to do with the fact that the old fill valve over-filled the bowl a little, which allows more water to go down the drain. When I installed the unit and new fill valve, I set the water level in the tank at the same height where it was before. This resulted in unsatisfactory results. Even with both adjustment dials turned to MAX, the toilet would not flush. So, I adjusted the new fill valve to fill the tank to the "max fill" line, which is engraved into the inside of the tank. This allowed me to adjust the dials to allow a complete flush with both liquid ("half flush") and solid ("full flush") waste. The liquid adjustment was easy... if three sheets of toilet paper go down, the adjustment is correct. The solid adjustment took an extra day or two of using the toilet. I had to increase the solid adjustment once, in order to ensure a complete flush. I guess that was an extra-high-fiber day. LOL I eat lots of vegetables. I have been using it now for almost a week, and it works perfectly. As they say, the proof is in the pudding. So, I wanted to measure the water savings. Your results will vary, because each model of toilet has a different flush performance. My toilets are not the best performing water-saving toilets I've ever owned, but I'm a renter now... and I think my landlord would probably get upset if I replaced the whole toilet! With my current settings, a "full flush" uses 1.6 gallons, exactly what the toilet is rated to use. This is a savings of 0.3gpf, compared to what the toilet used previously. A "half flush" uses 1.3 gallons. While this isn't a huge difference (certainly not "half"), it is something... and would probably be better with a toilet which has a better flush performance score (yes, that's actually a thing). I used to own my home, and I installed toilets which had a flush performance of 10.0 (the highest possible). I think that those toilets would probably flush liquids with far less than 1.3 gallons. Unfortunately, I never installed a duo-flush valve in them. At my new place of residence, the cost of water is double what it was at my old place... so I'm looking at ways to save water. So... the important question is: "Is it worth the money to buy this device?" ... I estimate that this unit will save me about 50 gallons per person, per month. At my current cost of water, that's about $1.00 per person, per month. Since I only paid $18.99 for this thing, it will pay for itself in: 19 months in a 1-person household 9.5 months in a 2-person household 6.33 months in a 3-person household 4.75 months in a 4-person household etcetera ... Of course, if you buy two or three of them for all of the toilets in your house, you need to double or triple the number of months I mentioned above. In my case, yes... it was worth the money. I would have liked to see a lower gpf for liquid flushes, but... overall.. I'm satisfied. Oh, I should mention something else. Some reviewers complained that the handle seemed flimsy. I disagree. I think it is sturdy enough. Maybe they didn't tighten it enough, allowing it to wobble in the hole?

## Frequently Bought Together

- Fluidmaster 550DFRK-3 DuoFlush Complete Fill and Dual Flush Conversion System, 2
- Fluidmaster Tank To Bowl Bolt & Gasket Kit 6102
- Fluidmaster 507AKP7 PerforMAX Universal High Performance 2-Inch Toilet Flush Valve Repair Kit with Gasket and Bolts

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*Product available on Desertcart Belgium*
*Store origin: BE*
*Last updated: 2026-06-19*