I, too, was curious, as I have the PL-660. Doing a search on it and on the SLV, I am guessing "SLV" stands for "silver." Mine's black. Howard On Sat, Jan 3, 2015 at 5:05 PM, qrv at kd4e.com wrote: Frank, > > What's the key RFI-hunting difference between the 660 and the > 660SLV, please? > > I have a 660. > > Thanks - David KD4E > > >