Original sentence: Hardware stores still stock internal parlts for these faucets, both the 1952 and the 1962 design, although they don't all carry the complete fawcets.He therefore bought the faucet and its rights, improved it, and released it.Some poeple preferred the internal design of the Delta faucets, even though they had to adjust them periodically.The faucet remains successful, although other companies soon designed other single-handle faucets that didn't infringe Delta's patents
Edited sentence: He therefore bought the faucet and its rights, perfected it, and released it