The Large 3″ Tank to Bowl Gasket is designed to fit specific toilet models that were made after 2000. The universal sponge rubber design measures: 3″ inner diameter, 4-1/4″ outer diameter and 1-1/8″ thick. The tank to bowl gasket fits most 3″ two-piece toilets including, but not limited to: American Standard Cadet 3 (4019, 4021), Champion (4260, 4272, 4281), Champion 4 (4077, 4266, 4272, 4281), AquaSource (AT1201, AT 1203), Crane Sure Flush (31242), Eljer Diplomat (4019, 4021), Stratus (4007), Titan (141-0777), Titan 4 (4272), Ferguson Pro Flo HET (PF9400), Gerber Avalanche (28-890, HE-28-890), Jacuzzi Era (BK37), Espree (EZ36), Maxima (EZ37), Perfecta (EZ33, GU04959), Prestige (GV80), Mansfield Barrett (106), Summit (386), Maverick (112), Waverly (3195), Pegasus Westminster (164-146), TOTO Drake (743S), Eco Drake (743E), Tuscany Sereno (11-105). Please note: tank to bowl gasket is not compatible with Kohler toilets. Easy to install.