Maria & Walter CMYK

History of Düring AG

The brand durgol

Maria Düring-Keller laid the foundation stone of the company when she developed the descaling agent called durgol more than 70 years ago. durgol has been the reliable helper against limescale for decades and is the market leader in Switzerland and Austria. The Swiss quality product removes limescale quickly and thoroughly. For a well-kept household and perfectly maintained household appliances - wherever limescale is undesirable. You can find out more about the history of Düring AG and the durgol brand at

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WC Ente

Inventor of the famous "toilet duck"

Thanks to his restless inventive spirit, Walter Düring, the son of the founder Maria Düring-Keller, succeeded in inventing the famous toilet duck in 1980. It revolutionized toilet cleaning and achieved worldwide success. The first recipe came from Vera Düring, Walter's wife. Other variants and product forms followed over the years. Since the sale of the "WC-ENTE" trademark rights at the end of 2008, Düring AG has concentrated fully on its core business, descaling. The freed resources have since been used for the development of further innovations.