Ball and collet provides 3 rotational and 1 prismatic degrees of freedom around a ¾" shaft. (I use a 2' length of 1/16" wall aluminum extrusion from Home Depot) Clamp the collet with uniform pressure to secure the rod in any orientation
The phone holder uses a standard ¼" hex head bolt and nut 2.5" or greater for the knob and two ¼" bolt and nuts to attach the ball mount to the ¾" shaft.
The author hasn't provided the model origin yet.
