Compatible with for IW3511. Please note check vacuums in size, model before order. combo set to keep your room clean and comfortable. Washable & Reusable. Rinse with clean water and let it completelyair dry before reusing filter. For optimal performance, it is recommended to change this filter set once every 1-3 months. Easy to Replace and Install, When it needs to be replaced, just remove and replace from your machine equipment, no tools required. Please note; the physical slightly color difference or difference, does not affect the use, please do not mind, ! Material: plastic colour: As Shown Package Contents: 2 x Black filter elements 2 x black filter cotton 2 x aromatherapy 2 x curved filters 2 sets filter cotton 2 x high efficiency filters Only the above package content, other products are not included. Note: Light reflection 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.