Check the listing for details. VIVOSUN 4"/6"/8" PP Cotton Prefilter 1.8mm for Carbon Filter Black/White Updated. Color: White/Black, Condition: New. Listed at 9.99 USD. VIVOSUN Updated Black / White Pre-filter for 4"/6"/8" Carbon Filter Durable: Made of high-quality PP cotton, it is durable and can withstand multiple cleanings without deformation and can be used repeatedly Reliable Protection: 1.8 mm thickness protects the charcoal bed from hair, dust, lint, pollen and other large particles Good Filtration: Breathable material allows unobstructed passage of air for proper air filtration and odor control, ensuring optimum air quality Perfect Fit: Filtrates larger particles from the air, preventing them from getting into the carbon filter and causing blockages, extending the lifespan of carbon filter; Available in a variety of sizes to meet the needs of different sizes of carbon filters Easy to Install: The sleeve is made according to the shape of the carbon filter, which means that you won't need any extra tools to install or remove it