This is an addition to 6d6178's Modular Mounting System that allows you to connect the system to a Desk Clamp that accepts a 0.5in pin.
There is enough clearance for the pin to allow the it to spin freely without wobbling around too much.
Printed in PETG with default Prusa Slicer settings and Organic supports.
The author remixed this model.
This adds a 0.5in pin to attach the system to a desk clamp