FOX High Speed Needle
In FOX fashion, they made many varations of simular parts. This one has a 6-40 thread and a 1/16" diameter needle that extends out of the knob around .580"
We found another needle know with an 8-60 thread so you may waht to check yours.
A 6-40 thread measures about .135" dia and an 8-60 is about .165" dia