I have got this before and it generally cleans ALL COFFEE MACHINES NOT JUST DRIP INCLUDING KURIEG AND KNOCK-OFF KURIEGS AND ESPRESSO MAKERS. It is basically Food Grade Citric Acid. I live in Wisconsin where the hardness scale is a 9 and it is because of all the limestone which creates good artisinal well and Springwater but is absolutely devastating on everything. I have used it to clean my kurieg with tis before. All you have to do is add it to the reservoir and brew hot water and re rinse and repeat. It takes anywhere from 25 to 45 minutes.