
Kohler GP89825
Score: 75/100
Kohler 1138648
Score: 75/100Rankings

The Kohler K-GP89825 is a genuine 2-inch replacement flapper designed exclusively for the Kohler Portrait one-piece toilet model K-3357. It features a shark-fin design with an adjustable chain and is constructed from premium, corrosion-resistant rubber to ensure durability. This part serves as a direct replacement for several discontinued flapper models, ensuring proper function for the specified model.

The Kohler Genuine Part 1138648 Flapper Assembly is an OEM replacement component designed for Kohler toilets, specifically compatible with two-piece models manufactured prior to 2004 that utilize a 2-inch flapper design. It controls water flow from the tank to the bowl and is constructed from durable, chemical-resistant materials to ensure optimal performance and warranty protection. This part is essential for routine maintenance and DIY repairs on compatible units like the San Raphael K-3722.
| Attribute | ![]() | ![]() |
|---|---|---|
2 inchesbest | 2 inchesbest | |
1 countbest | 1 countbest |
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| Attribute | ![]() | ![]() |
|---|---|---|
Material & Durability(4) | ||
Material | Rubber | Chemical-resistant |
Seal Type | Shark-fin | null |
Hard Water Resistance | true | null |
Water Resistance | true | null |
Design & Features(4) | ||
Chain Material | Standard | null |
Chain Adjustability | true | false |
Installation Type | Standard | Direct replacement |
Flapper Type | Shark-fin | Flapper Assembly |
Packaging & Support(1) | ||
Warranty Period | 1-year limited | null |
Compatibility & Fit(3) | ||
Flush Valve Compatibility | 2 inches | null |
Toilet Type Compatibility | Kohler Portrait K-3357 | Two-piece |
Flush Valve Size | 2 inches | 2 |


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

Professional reviewers and editors do not provide specific quotes or in-depth testing results for this product. Retailer descriptions and Kohler service documentation emphasize its status as a genuine OEM part, highlighting the reliability of its premium materials and USA manufacturing. It is confirmed as the direct replacement for older flappers in Portrait toilets, ensuring proper function for the specified model.
Consumer feedback is limited, with Home Depot listing 37 reviews but lacking specific quoted praise or complaints. Common implied praise centers on the reliable fit and durability for K-3357 owners. Recurring issues in Q&A sections involve frequent compatibility questions, with confirmations that the part does not fit non-Portrait models. There are no widespread complaints regarding leaks, short lifespan, or installation difficulties.

No independent professional reviews, editorials, or expert analyses from recognized plumbing authorities or consumer reports are available in the source data. Retailers and Kohler's service pages describe the part positively as an essential component for reliable flushing and meticulously designed for performance, emphasizing its OEM quality.
There is a complete absence of consumer reviews, ratings, or testimonials in the available data. One listing explicitly notes zero customer reviews, making it impossible to identify common praise, complaints, or recurring themes from everyday users.

