Cadet 3 Flowise Flapper Assembly Compatible with Cadet 3 Toilets (2852.000, 4000.101, 4007.101, 4021.128) Genuine American Standard repair part Call American Standard's Customer Service at 1-800-442-1902 to see if this part will fit your American Standard product For 4021N model, please use 7381193-200.0070A Check your repair part information for compatibility