**THIS ITEM IS NO LONGER AVAILABLE** Amaircare Model 4000 Complete HEPA Replacement Kit. Should be replaced every 2-5 years to maintain filter effectiveness! This complete replacement HEPA kit is direct from the manufacturer, Amaircare, and they recommend that it be replaced every 2-5 years so that your HEPA system can continue to operate effectively. It includes 1 pre-filter, 1 HEPA cartridge and 1 carbon filter.