Abstract: This invention is drawn to a filter assembly for use in conventional floor registers in HVAC systems. The assembly includes a diamond shaped center rod which splits the air flowing through the filter assembly and supports a pair of hinged doors which open during active periods of the HVAC cycle and close during the dormant period of the HVAC cycle. A sponge-like, tacky adhesive filter is positioned on the top surface of each door to filter dust or dirt particles that drift into the register during the dormant period of the HVAC cycle.