Replacement Filter Suit for Rowenta RO7611EA RO7634EA RO7623EA RO7647EA RO7663EA RO7676EA RO7681EA Silent Force Cyclonic Compare ZR903701. We recommend changing the filter every 3-6 months to ensure proper performance perfect. It also depends on the frequency of use. Blocks fine particles and floating dust and avoids secondary pollution. Helps protect our home from dust, pollen and mold spores. Package contains 2 HEPA filter boxes, 2 sponge filters. We offer the best customer service and the highest quality for every customer. Note: The data is all manually measured, please allow 1-3cm error, due to the difference in light and display, there will be a certain color difference, the actual object received shall prevail .