Fluidmaster 502P21 PerforMAX Universal Toilet Flapper 2 Inch
- 2 inch flush valves only
- Adjustable frame design
- Rubber flapper, red
- 22.68 grams, 4.9 x 3.5 x 3.5 inches
- 5 year warranty
Last refreshed Sep 8, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A universal rubber toilet flapper made for two inch flush valves, with an adjustable frame. It does not fit other valve sizes, so check your flush valve before buying.
As an Amazon Associate I earn from qualifying purchases. ProductDome earns a commission when you buy through links on this page.
ASIN: B000BVS3H0Model: 502P21Category: Toilet Flappers
Overview
Inside a toilet tank, this red rubber flapper covers the flush valve opening and lifts when you flush. An adjustable frame lets it suit different valve styles, and the listing describes a barb inlet and flange outlet.
Replacing a worn flapper is often the quickest fix for a running toilet, and a universal frame handles different tank layouts. The limit is valve size, since the listing covers two inch valves only.
Who it's for
Homeowners and landlords fixing a running toilet. Anyone unsure of the valve size should measure first, since the flapper does not adapt beyond the listed fit.
Pros and cons
- Universal adjustable frame
- Five year warranty
- Two inch valves only
- Not a fill valve
- Installation steps not listed
- Product only, no extras
Performance notes
The flapper lifts to release tank water and drops back to seal the valve, so seal quality decides whether the toilet runs on after a flush. Rubber wear and mineral buildup on the seat reduce the seal over time. The adjustable frame helps the flapper line up with the valve.
Where it stands among toilet flappers
- #2 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 | Fluidmaster |
|---|---|
| Model | 502P21 |
| Dimensions & fit | |
| Outlet Connection Size | 2 inches |
| Inlet Connection Size | 2 inches |
| Item dimensions | 4.9 x 3.5 x 3.5 inches |
| Item weight | 22.68 grams |
| Construction & materials | |
| Material Type | Rubber |
| Exterior Finish | Metal |
| Included components | |
| Included Components | Product Only |
| Number Of Packs | 1 |
| Warranty & support | |
| Manufacturer Warranty Description | 5 year |
| Other details | |
| Valve Type | Flapper |
| Outlet Connection Type | Flange |
| Inlet Connection Type | Barb |
| Connector Type | Mechanical |
| Item Type Name | toilet-replacement-parts |
Frequently asked questions
Is the Fluidmaster 502P21 a complete toilet repair kit?
No. The listing says product only, which is the flapper.
What size valve does the Fluidmaster 502P21 fit?
The listing says two inch flush valves, and gives a 2 inch inlet and outlet size.
What is the Fluidmaster 502P21 made of?
The listing gives rubber.
What warranty comes with the Fluidmaster 502P21?
The listing gives a 5 year warranty.