This Carpet Pro HEPA filter set comes with a standard pre motor filter as well as a HEPA post motor filter. Combined these 2 filters relieve homes of both large and fine particles making this the ideal set for allergy and asthma sufferers. These filters are designed to fit into CPU-1, CPU-1T, CPU-2 & CPU-2T vacuum models. Recommended replacement is every 12 months except for homes with extreme allergy sufferers, where we recommend every 6 months. Genuine Part # CPU12-F.