The E406288 is a Universal Tank-Bowl Gasket. It fits all two-piece toilets EXCEPT Mansfield. Fits Flushmate Systems 500, 501, 501A, 501B, 503, 504, F31A, F3A, F3AR, F3C, F3CR, F3CC, FCE, F3ER, F31, F3G, F3G2, F3L, F3LR, F3, F3R, F3M, F3MP, F3MR, F3O, F3U, F3UR, F3Z, F32, F3K, F3KR, F3G4, F3G3, F3GR, F3K1, F3K2, F4A, F4AP, F4P, F4L, F4LR, F4N, F4B, F4C, F4K, F4KR, F4MP, F4J, F4M, F4V1, F4V2, Fits all American Standard, Briggs, Caroma, Ceralux, Eljer, Gerber, HCG Hocheng Corp, Kohler, Lamosa, Mancesa, Niagara, Orion, Peerless, St. Thomas, Vitra, Vitromex, Vortens, Western Pottery, Xinqi