Found it.
It is held up by the pop-up in water, so the curve link is not quite so severe as it looks.
The boom is a doubled over length of Smakeskin, and the pop-up weights are free running.
The hooklink section goes through the swivel exactly like a 360.
Yes, it is on a helicopter set up, Solar Unleaded needle knotted to the mainline, and I had cast it to around 115metres, just under the outer branches of a tree on the island where I'd seen a few fish, so it's tangle free.
The fish I had runs from, absolutely nailed.
You could quite easily swap the boom section material.