Product Description"The Korky Ultra High Performance Flapper is the most universal 2 inch flapper available. The flapper adjusts to match original toilet settings and eliminates water waste by decreasing the amount of water flushed. Ideal for all standard 2 inch toilets, including: 1.28, 1.6, 3.5 and 5 gallons per flush (gpf). The exclusive longest lasting red rubber resists chlorine, bacteria, city water treatment, hard water, and well water. Recommended by the Clorox help line, this Korky flapper is proven longest lasting. The adjustable flapper has multiple settings to ensure it fits popular 2 inch toilet models. Made of flexible rubber for a tight seal and easy to install, the 100 includes: (1) Adjustable Flapper and (1) Stainless Steel Chain.The 100 toilet flapper fits the following toilet brands, models and tank numbers: Fits Aqua Source: Aqua Project Source (CP-321) | American Standard: Cadet (4029, 4078, 4083, 4053, 4650), Evolution 2 Flowise (4061), Monarch (4003), Mainstream (4061) | Crane: Galaxy (3742) | Gerber: Viper (28-590) | Glacier Bay: WCRS1 | HD Supply: Seasons (564830) | Kohler: Portrait (K-4590), Wellworth (K-4620, K-4512, K-4519) | Seasons: Anchor Point (564830) | Sterling: Riverton (404522), Stinson (402091), Windham (404555) | TOTO: Carusoe (706), and many more!"From the Manufacturer"The Korky Ultra High Performance Flapper is the most universal 2 inch flapper available. The flapper adjusts to match original toilet settings and eliminates water waste by decreasing the amount of water flushed. Ideal for all standard 2 inch toilets, including: 1.28, 1.6, 3.5 and 5 gallons per flush (gpf). The exclusive longest lasting red rubber resists chlorine, bacteria, city water treatment, hard water, and well water. Recommended by the Clorox help line, this Korky flapper is proven longest lasting. The adjustable flapper has multiple settings to ensure it fits popular 2 inch toilet models. Made of flexible rubber for a tight seal and easy to install, the 100 includes: (1) Adjustable Flapper and (1) Stainless Steel Chain. The 100 toilet flapper fits the following toilet brands, models and tank numbers: Fits Aqua Source: Aqua Project Source (CP-321) | American Standard: Cadet (4029, 4078, 4083, 4053, 4650), Evolution 2 Flowise (4061), Monarch (4003), Mainstream (4061) | Crane: Galaxy (3742) | Gerber: Viper (28-590) | Glacier Bay: WCRS1 | HD Supply: Seasons (564830) | Kohler: Portrait (K-4590), Wellworth (K-4620, K-4512, K-4519) | Seasons: Anchor Point (564830) | Sterling: Riverton (404522), Stinson (402091), Windham (404555) | TOTO: Carusoe (706), and many more!"