Vornado® MD1-0023 Replacement Carbon Filter, 2-PackYour air purifier will reach peak performance with these vornado pre filters. These carbon pre filters prolong the life of your hepa filter while ensuring more harmful particles are caught. Keep the air in your home clean with these charcoal filters. Replacement carbon filter Replace your filter every 3 months with regular use 2 filters in 1 Activated coconut carbon prefilter traps odors & other organic compounds Helps extend the life of the hepa