These may cost a few shekels more than a nut, however, since you bought the Incra fence, I'm assuming convenience is a greater priority.
They are both available from Rockler (cost a bloody fortune shipping to Aussieland)...
The knob is a slip knob that's great for long threaded rods when you need to physically remove the knob and not just loosen. The other gizmo works on a cam system and a breeze to select the appropriate force, without tools... I think there's an Incra version, hmmm, not sure as there is no branding... though more the Woodpecker$ colour.
If your first cut is too short... Take the second cut from the longer end... LBD
