The Lippert Flow Max RV Toilet Ball Seal is a genuine replacement part and is compatible with all RV toilets using a 4.02" OD x 2.76" ID seal.• Replacement ball seal for Flow Max RV toilet• Compatible with all RV toilets using a 4.02" OD x 2.76" ID seal• Easy to install Easy to install | Lippert Flow Max Replacement RV Toilet Ball Seal