A rope is probably the oldest watersport 'do it yourself', device. Using the rope, one can get fun being pulled by the boat. Everybody that tried it had faced two major problems; water build up in front of the face, making difficult to breath and unpleasant feeling, of the rope cutting into the hands. Booth problems are increased by increased speed. As speed brings fun it is evident that fun potential is limited

In order to cope with the problem, one 'do it yourself' solution is to use some kind of a board, where the rope will be wounded around the board (see image on right) and board will be used as handlebar allowing more ergonomical grip.
Additional benefit is that mentioned board can be used as control surface allowing to chose, to be pulled over the surface, or go under the surface. Once this was realised first patents started to appear. During R&D ,related to REZRON concept, oldest patent, found to deal with the subject, are US4207829 ili US5655939 .

Adding simple board will not solve problem of the wave build up.
Three years ago R&D, aimed to solve this problem, was started. First prototype resembled a polycarbonate pyramide look like deflector that protected user from the wave build up. Left fIgure shows view through the deflector right side, during surface ride. Some other authors proposed deflectors optimised for underwater performance as one described in US5007871 After several prototypes REZRON concept was developed and patent is filed. Protected form is optimised for underwater and on water performance