
Fluidmaster PerforMAX Flapper
Score: 88/100Fluidmaster 506 Flapper
Score: 70/100Rankings

The Fluidmaster 502P21 PerforMAX is a universal, adjustable 2-inch toilet flapper designed to resolve weak flushes, running toilets, and water waste in toilets with 1.28, 1.6, or 3.5+ GPF ratings. It features a dial-adjustable mechanism for customizing flush volume, Microban antimicrobial protection, and a solid frame to prevent twisting during operation. It is best suited for homeowners with most 2-inch flush valve toilets experiencing weak flushes, running toilets, double flushes, or high water use.
The Fluidmaster 506 is a universal, non-adjustable 2-inch flexible frame flapper designed for older pre-1994 toilets with 3.5+ GPF flush valves. Its main trade-off is the lack of adjustability and modern durability features, making it less suitable for water conservation. It is best suited for DIY users replacing flappers on older, high-volume toilets with irregular valves.
| Attribute | ![]() | Fluidmaster 506 Flapper |
|---|---|---|
2 inchesbest | 2 inchesbest | |
1 countbest | 1 countbest |
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| Attribute | ![]() | Fluidmaster 506 Flapper |
|---|---|---|
Material & Durability(5) | ||
Material | Rubber/Plastic | Rubber |
Seal Type | Solid Frame | Flexible |
Chlorine Resistance | true | Unknown |
Hard Water Resistance | true | Unknown |
Water Resistance | true | Unknown |
Design & Features(4) | ||
Chain Material | Standard | Unknown |
Chain Adjustability | true | false |
Installation Type | DIY | Standard |
Flapper Type | Adjustable Flapper | Flexible |
Packaging & Support(2) | ||
Warranty Period | 5 Years | 1 year |
Certifications | NSF/ANSI 61 | Unknown |
Compatibility & Fit(4) | ||
Flush Valve Compatibility | Universal | 2 inches |
Toilet Type Compatibility | Standard | Pre-1994 |
GPF Compatibility | 1.28-3.5+ | 3.5+ GPF |
Flush Valve Size | 2 | 2 inches |

Products in the top-left offer the best value (high score, low price).

Professional reviewers, including Home Improvement Expert Bob Vila, rate the Fluidmaster 502P21 as the best overall 2-inch flapper for addressing running toilets. It is praised for its ability to fix weak flushes, double flushes, and water waste. Manufacturer sources describe it as the 'gold standard' and 'high performance standard' due to its durability, adjustability, and Microban protection.
Search results do not provide direct consumer quotes or aggregated star ratings. However, implied praise from product pages suggests users value the reliable sealing, water savings, and ease of use for fixing running toilets. No recurring complaints are detailed in the available data.
Sources lack independent professional reviews or editorials; descriptions are primarily from the manufacturer and retailers. Fluidmaster categorizes the 506 as an all-rubber 2-inch non-adjustable flapper, noting that its flexible frame is specifically designed to suit oddly sized or angled valves better than rigid solid-frame types. It is emphasized as a simple and easy-to-install replacement for older toilets.
No consumer reviews, ratings, or testimonials are included in the available sources. Consequently, common praise such as ease of install and complaints regarding durability cannot be detailed with real user data.
