
Korky 54BP
Score: 75/100
Kohler GP1078441
Score: 85/100Rankings

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.

The Korky 54BP is a basic, universal 2-inch toilet tank flapper made of flexible, corrosion-resistant rubber, designed for standard plastic and brass flush valves. It offers a reliable seal and easy installation but lacks the premium durability and extended warranty of higher-tier Korky models. It is best suited for homeowners needing a cost-effective, quick replacement for standard gravity-fed toilets.
| 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(1) | ||
Material | Flexible Rubber | Rubber |
Design & Features(3) | ||
Chain Material | Stainless Steel | Standard |
Installation Type | Standard | Direct Replacement |
Flapper Type | Standard | Standard Flapper |
Packaging & Support(1) | ||
Warranty Period | 1 year | 1 Year Limited |
Compatibility & Fit(6) | ||
Flush Valve Compatibility | 2 inch Plastic/Brass | Kohler Class Five |
Universal Fit | true | false |
Flapper Diameter (inches) | 2 inches | 3.25 inches |
Toilet Type Compatibility | Gravity-fed | Two-Piece |
GPF Compatibility | 1.28-5 | 1.28 |
Flush Valve Size | 2 inch | 3.25 inch |


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

No independent professional reviews or editorials were found in the research data. Manufacturer and retailer descriptions position the product as the original toilet flapper and the choice of plumbing professionals since 1954, highlighting its universal fit, flexible rubber seal, and reliability for standard toilets.
Results contain no consumer reviews, testimonials, or forum discussions. Consequently, common themes, praise, or complaints from everyday users cannot be derived from the available data.

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.
“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.”


