For Sale is a 2.1 kHz SSB Roofing Filter (INRAD #2309) to replace the original Yaesu 3.0 kHz filter in the FTdx5000 radio. Not only is the bandwidth narrower, but the skirts are steeper. This is a direct plug-in replacement for the stock filter. In excellent working condition in original box. $100 including shipping. Mike W4UM