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 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 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!"