The rig is a further development of the Eighteen foot skiff rigs. The FRP topmast is relatively longer and the alloy lower mast is shorter, and some astute geometry in the primary shroud/forestay area has been added to fine-tune the way the forestay is kept taut when the mast bends.
The vang takes the form of a "ram vang" which pushes the boom down from above, rather than pulling it down from below. There are three reasons for this:
It is a safer system, in that it holds the mid-mast forward and so prevents mast failure from inversion if or when a flogging spinnaker snaps the masthead forward.
It opens up the forward cockpit so that the forward hand can move quickly and without obstruction from side to side as needed.
It enables the mainsail working area to be carried down to deck level. There is and astonishing reduction in drag of the design due to this and other innovations.