Assuming you are referring to the Jura Impressa E8 Automatic Coffee Machine:
The E8 is a high-end espresso machine that comes with a few automatic features. One of these is a built-in water filter. This filter is important for keeping your water clean and free of impurities, as well as for extending the life of your machine. The E8 also has a built-in coffee grinder, so you can make your own fresh grounds for each cup.
To use the cleaning tablet, simply remove the water filter and insert the tablet into the filter housing. Run a cleaning cycle without any coffee grounds. The tablet will dissolve and release its cleaning agents, which will clean the machine's internal components.