Rafter Ring
A spinnaker end is attached to the trailer end of each rafter. The spring loaded hook is cocked using a cable that runs thru the rafter. The hook snaps into the rafter ring securing the rafter to the trailer.
Frame rafters can be wired internally for 110v or 220v receptacles. Pneumatic tubing can also be threaded through the rafters to deliver compressed air or other gasses.