This is a remix of BertNijkamp pen holder to use it as an attachment to mediaman's Hero Me.
You'll still need to print the knob from here.
You'll also need 1x 16mm M3 screw and 1x M3 hex nut to mount the pen in.
To install it onto the Hero Me you can reuse existing screws from the stock setup
I couldn't find a better orientation to print this.
I printed it straight from the stl with support. It came out nice and the support was very easy to remove.