The Claris water filter cartridge was originally designed for Jura for their espresso coffee machines. It fits directly in the water tank and only filters the water as it is drawn into the machine, using the professional up-current principle. It is filled with organic material only without chemical additives. The Claris filter cartridge improves the taste of the water, helps protect your machine from limescale, and ensures its reliable operation. The filter cartridge will need to be replaced approximately every 6 weeks. Several other coffee machine manufacturers now produce machines that are compatible with the Claris water filter cartriges. The Claris Blue water filter is used for machines with a blue filter holder in the water tank, generally machines produced post-2009. If you look at the bottom of your old filter where it locks onto the machine it will have an hexagonal fitment if it requires a blue filter.