We live in Utah and the water here is FULL of minerals. Periodic descaling is a necessity for any item we use water in. Before these tablets, I used a vinegar baking soda mix to clean and descale our coffee pot and kettle. Although that was effective, it had to sit overnight, and it was a bit messy. These tablets are great! They removed the tea and coffee buildup and they removed the hard water spots. The results were especially amazing on our coffee pot. I filled each with 17 oz of water, dropped in a tablet, put on the lids and waited 25 minutes. After the time was up, I simply rinsed and dried them. Now they look brand new. 4 before and 3 after pictures are included so you can decide for yourself! I struggle with the cleaning of the bottom seam of the kettle, but these worked great!