Fluidmaster PerforMAX Flapper
Score: 88/100
Kohler GP1078441
Score: 85/100Rankings
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 Kohler GP1078441 is a genuine OEM replacement flapper designed specifically for Kohler two-piece toilets featuring Class Five flushing technology. Its key strength is the precise 3.25-inch rubber seal that effectively prevents phantom flushes and maintains high-efficiency performance. However, it is incompatible with non-Kohler models and may degrade faster in hard water environments.
| Attribute | | |
|---|---|---|
2 inches | 3.25 inchesbest | |
1 countbest | 1 countbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | | |
|---|---|---|
Material & Durability(2) | ||
Material | Rubber/Plastic | Rubber |
Seal Type | Solid Frame | Rubber |
Design & Features(3) | ||
Chain Adjustability | true | false |
Installation Type | DIY | Direct Replacement |
Flapper Type | Adjustable Flapper | Standard Flapper |
Packaging & Support(1) | ||
Warranty Period | 5 Years | 1 Year Limited |
Compatibility & Fit(6) | ||
Flush Valve Compatibility | Universal | Kohler Class Five |
Universal Fit | true | false |
Flapper Diameter (inches) | 2 inches | 3.25 inches |
Toilet Type Compatibility | Standard | Two-Piece |
GPF Compatibility | 1.28-3.5+ | 1.28 |
Flush Valve Size | 2 | 3.25 inch |
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.
“Perfect fit for my Kohler Cimarron-flush like new!”
“No more running toilet; lasted 2 years in hard water”
“Installed in 2 minutes, chain included.”
Plumbing experts and editors from sites like Ferguson and CPE Supply highly recommend this part as the definitive OEM replacement for Class Five systems. They highlight its precise 3.25-inch seal as critical for preventing phantom flushes and its durable rubber construction for resisting corrosion.
Everyday consumers generally report high satisfaction, with many noting that the flapper perfectly fits their Kohler models and restores the toilet to like-new flushing performance. Common praise includes the ease of installation and the elimination of running toilet noises.
