ADVANTAGES OF REUSABLE FILTER SLOTS - Reusable and easy to replace. They make filters for your machine more cost-effective and can reduce plastic pollution to be friendly to environment. FOAM POLLEN & ULTRA FINE - The foam version is to block particulate matter. The ultra fine version is to block fine particles. Use to the cleanest air. FOR HEALTHIER LIFE - kit is designed so as to you and your loved ones with the cleanest air to maintain the health of your lungs and keep the potential diseases from you. colour:Blue Material:filter sponge Package Contents: 6 x Disposable Ultra Fine Filters 2 x Pollen Filters Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.