High performance: the filters maintain the cleaning performance of your robot, which can sweep tiny dust and bacteria generated during cleaning to reduce secondary air pollution.Block and reduce dust damage to sensitive parts of our machine. Maintenance: Replace the filter depending on your usage frequencey to keep your home robot operating at performance. It's better to replace it every 1-2 months. How do replace your filter: Take out the dirt bin. Remove the filter from dirt bin. Replace the new filter. Put the dirt bin back into its slot on top of the robot. colour: blue + White Material: plastic Package Contents: 2 * Primary Filter Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. High performance: the filters maintain the cleaning performance of your robot, which can sweep away tiny dust and generated during cleaning to reduce secondary air pollution.Block and reduce dust damage to sensitive parts of our machine. Maintenance: Replace the filter depending on your usage frequencey to keep your home robot operating at . It's better to replace it every 1-2 months.