Structure:microfiber and synthetic fiber Usage:Filter debris in water and humidify the air,99.5% for 0.3 Micrometre particle99.5% for 0.3 Micrometre particle size:22.8cm Material:Superfine fiber + synthetic fiber colour:Blue Package Contents: 1 x 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.