I just dug one out of the attic, and it has "30 - 150" marked in
pencil on the side, which I assume is the capacitance range
in pF. It has 11 moveable plates.
IIRC this came from one of the "fixed" VFO capacitors, that
was adjusted during alignment, then locked in place. It has
only a very short stub of a tuning shaft, enough for the
shaft lock, but not quite enough for a comfortable knob.