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Fluidmaster Toilet Fill Valve

Fixes a running or slow-refilling toilet by replacing the worn fill valve inside the tank.
Fluidmaster MPN 400ACN3P5 In Stock & Ready to Ship
$24.99
Free shipping on orders over $75
Ships within 24 hours · most orders arrive in about 2 business days

About Product Overview

When a toilet won't stop running or refills too slowly, the fill valve is usually the part to blame. This Fluidmaster toilet fill valve replaces a worn or failing valve and restores normal tank refill after each flush. It's sold as the valve only, so no handle or extra hardware comes in the box - just the part that does the job.

  • Brand: Fluidmaster
  • Product type: Toilet fill valve
  • Dimensions: 3.5" x 7.75" x 13.05"
  • Weight: 1.62 lbs
  • Country of origin: Mexico

The Details Specifications

Brand Fluidmaster
Model / MPN 400ACN3P5
UPC 039961400031
Weight 2 lbs
Safety Data Sheet (SDS) Manufacturer documentation · opens in new tab
Price check

Go ahead. Check.

You're going to price-check us against Amazon, Home Depot, and Lowe's. Everybody does. Good — open all three tabs. We'll wait. Then look hard at what you're actually being handed over there.

On Amazon, start with these four questions before you click buy.

01

Who's actually selling it

The brand name is on the listing. A different company is in the seller field. Those aren't the same thing, and the second one is who you're buying from.

02

Whether the warranty survives

Most manufacturers only honor a warranty when the unit came through an authorized dealer. We're authorized for Fluidmaster. A third-party marketplace seller usually isn't.

03

Where the box came from

Gray-market stock, returns repackaged as new, and outright fakes move through marketplaces constantly. It all looks identical in the photo. It stops looking identical when it fails.

04

Who you call when it breaks

Ours is a phone number with a person behind it who has held this product. M–F, 6 AM – 5 PM Pacific. (866) 469-8556

The big boxes don't care if your hardware store survives.

Amazon, Home Depot, and Lowe's are built to pull every hardware dollar out of your town. When the local shop can't keep the lights on, the counter where somebody actually knew which part you needed goes with it. We're built the other way: real brands so you're never stuck on a marketplace, and a straight answer to buy it down the street when that's the better call. Support independent hardware — it doesn't restock itself.

Why we tell you to shop local
Authorized dealer · Fluidmaster

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