
Fluidmaster PerforMAX Flapper
Score: 88/100
Hibbent Toilet Flapper
Score: 80/100Rankings

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 Hibbent 2 Pack Toilet Flapper Replacement is a blue rubber flapper designed as a direct replacement for the Gerber 99-788 model, featuring durable material and no-tool installation. It is limited to specific Gerber models, which restricts its universal applicability. It is ideal for DIY repairs in homes with city, hard, or well water, offering a quick, tool-free fix that meets US/Canada plumbing standards.
| Attribute | ![]() | ![]() |
|---|---|---|
2 inches | 3 inchesbest | |
1 count | 2 countbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Material & Durability(1) | ||
Material | Rubber/Plastic | Rubber |
Design & Features(3) | ||
Chain Material | Standard | Stainless Steel |
Installation Type | DIY | No-Tool |
Flapper Type | Adjustable Flapper | Flapper |
Packaging & Support(2) | ||
Pack Quantity (count) | 1 count | 2 count |
Certifications | NSF/ANSI 61 | US and Canada Plumbing Code Standards |
Compatibility & Fit(4) | ||
Universal Fit | true | false |
Flapper Diameter (inches) | 2 inches | 3.0 inches |
Toilet Type Compatibility | Standard | Gerber 99-788 |
Flush Valve Size | 2 | 3 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.




Installation tutorials and video demonstrations highlight the straightforward nature of the replacement, praising the quick setup and the reliability achieved through proper seal cleaning.
Product pages imply positive sentiment regarding leak prevention and water savings, with video demos suggesting that users find the chain adjustments user-friendly and the overall installation process positive.