This elongated toilet bowl is designed to work with American Standard toilet tank models 1021.016.020 and 4021.128.020. Purchased with the toilet tank this toilet bowl will form the following American Standard toilet models: 2383.012.020 and 1832.128.020. The American Standard toilet bowl also inhibits the growth of stain and odor causing bacteria on the surface with a unique antimicrobial surface called EverClean. Check out all of American Standards bathroom and kitchen fixtures to see a complete list of lavatory and kitchen products available for your home.