TOTO THU500S Replacement Flapper 3 Inch
- 3 inch flush valve size
- Polypropylene body, rubber sealing surface
- Chain and instructions included
- Adjustable for various TOTO tanks
- 1 year limited warranty
Last refreshed Sep 8, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A replacement flapper for select TOTO tanks with a three inch flush valve. Match your tank model against the part numbers it replaces before buying, because it only fits that range.
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ASIN: B076KL3K87Model: THU500SCategory: Toilet Flappers
Overview
A homeowner with a leaking or worn toilet flapper gets a direct TOTO replacement here. It has a polypropylene body with a rubber seal, comes with a chain, and is adjustable to suit different tanks.
The reason to buy is a fitted part from the toilet maker, with setup instructions written for TOTO tank models. The limit is its narrow scope: it fits select three inch flush valve tanks only and is not a universal flapper.
Who it's for
A toilet that runs on or loses water between flushes is the setting, provided the tank is a listed TOTO model. Plumbers working on mixed brands should keep a universal part, since this one is matched to a specific part number list.
Pros and cons
- Made for TOTO flush valve tanks
- Instructions for TOTO tank models
- Rubber seal on the sealing surface
- Fits select TOTO models only
- Not a universal flapper
- Part number match must be checked
Performance notes
The rubber sealing surface presses on the valve seat to stop water from leaking into the bowl, so a worn or warped seat will still leak. The chain length sets how long the flapper stays open during a flush. Adjustable tuning lets you match the flush time to the tank.
Where it stands among toilet flappers
- #4 most-searched brand and model of the 11 toilet flappers lines we track (by search demand, not sales).
From the specs of the 31 toilet flappers we list; not a test result.
Specifications
| Brand | Toto® |
|---|---|
| Model | THU500S |
| Dimensions & fit | |
| Outlet Connection Size | 3 inches |
| Inlet Connection Size | 3 inches |
| Flush valve size | 3 inches |
| Item Dimensions | 4.75 x 3.5 x 2.5 inches |
| Item Weight | 0.27 g |
| Construction & materials | |
| Material Type | Plastic |
| Body material | Polypropylene |
| Included components | |
| Number Of Pieces | 1 |
| Included Components | Flapper, chain, set-up instructions |
| Warranty & support | |
| Manufacturer Warranty Description | Manufacturer One Year Limited |
| Other details | |
| Valve Type | Toilet Flapper Valve |
| Inlet Connection Type | Rubber Flapper |
| Item Type Name | Replacement Flapper for Select TOTO 3 Inch Flush Valve Tanks |
| Outlet Connection Type | Standard 3-inch Connection |
Frequently asked questions
How do I install the TOTO THU500S flapper?
The listing says the flapper includes a chain and instructions for set-up specific to the TOTO tank model. It is adjustable for various tanks, so follow those instructions for chain length.
Will the THU500S fit any toilet?
No. It is for select TOTO tanks with a three inch flush valve and replaces specific TOTO part numbers listed in the product description.
Is the chain included?
Yes. The listing says the flapper includes a chain.