Cost-effective component filter kit with 4 pieces of ultra-fine filters.Easy to replace.The ultra-fine powder-foam version prevents large particles. The ultra-fine version will block fine particles. Use them together to provide the cleanest air.Healthier clean air-our kits are designed to provide you and your loved ones with the cleanest air to stay healthy.This filters are only for Respironics DreamStation CPAP Machine.Performance: Dust filter cottonApplicable object: airUses: air filtrationColour: blue + whiteMaterial: filter cottonSize: about 6.8 x 6.8cmPackage Contents:4 x filtersOnly the above package content, other products are not included.Note: Light shooting 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.