Sea Horse Toilet Seats: Made of High Grade Polymer this seat is designed for maximum strength & durability & does NOT yellow over time like most polymers. Fits over standard size toilet bowls & comes in a variety of designs. Cast within the seat the stabilizing bumpers prevent rocking & keep the seat safely in place. Solid brass PVD swivel hinges are easily adjustable 3 5/8 in. to 7 1/2 in. & easier to clean. Physical Vapor Deposition protects brass hinges from tarnishing for years to come. Seat measures: 15 13/16 in. x 14 9/16 in. Lid measures: 14 5/16 in. x 13 1/8 in. Round shape.