Printed in ABS and with supports on the inside.
Strain relief shroud/jacket for DC screwjack plug.
First put large heatshrink over wires. Pull wires through.
Screw into jackplug. Put together and heatshrink the jacket and wires together.
You could also just push hotglue into the hole between jacket and wire to lock it in.
The author remixed this model.
My connector did not fit. Created new one with inspiration from this