The HEPA filter located in the back is responsible for cleaning the outgoing air.  Especially helpful for those who are suffering from household allergie. After 3-6 months of avarage use, rinse the filter following the instruction of the Usen Manual. Its performance may drop significantly after 3-4 rinses, thus it needs to be replaced.

Use the device with model specific accessories and spare parts only. For further information read the Intruction Manual of your product.