29 5/16-Inch Length by 18-15/16-Inch Width by 28-13/16-Inch Height Overall Dimensions * Large 3-1/4-Inch Canister Flush Valve Features a Powerful Jet Action, Providing Rapid Water Delivery from Tank to Bowl * High-Efficiency System Offers Bulk Flushing Performance and Best-In Class Cleanliness * Significant Water Savings of as Much as 16,500-Gallon of Water Annually Over a 3.5-Gallon Toilet * Meets Strict Flushing Performance Guidelines Established by the EPA"s WaterSense Programs