Personally designed custom aftermarket Uniden Bearcat Trunktracker BC 780 XLT Scanner Replacement Knob Set.  Includes 1 each: Volume, Squelch, VFO/Select knob.  Designed to be a direct fit onto the scanner without the metal collar from the old knobs.  Installation is easy with pressing them on over the stem (Volume knob will likely need to be started at a corner before being squared up due to the stretch of the knob design.

The 780 is a great unit, too bad the Uniden knobs seem to have a history of falling apart.

***The metal retainer clip from inside the old knobs must be removed from the scanner stem otherwise these will not fit***