The RPS Central Hepa System is an air purifier that attaches to your HVAC system. It has a washable pre filter, which helps capture large particles, and a secondary charcoal filter that removes orders and gases. Additionally, the True Hepa Filter removes all particulate matter up to .03 microns in size, which pulls 30% of the dirty air through 100% of the medical grade filter without causing a pressure drop. A free annual consult is included with the purchase of this product.