This diagram comes from Steve Coopers book "Shark fishing from Shore" about 1980's I think it is.
Operates on the same principle as the standard paravane, except that it runs out horizontally, Ideal for taking big baits out when there is a strong long-shore current.
Wind has no detrimental effect.
The paravane is attached to the top link of your mainline swivel.
I have tried a smaller version (about 12"x 6") and it works reasonably well, and once tuned for the conditions should get a fair distance offshore before feathering out.
Rather than the masonite, I used an offcut of perspex sheet as I was running a lighter rig at the time, but will be trying the full Monty this summer for my bitey sessions up North.