Parabolic Stringers
Parabolic Stringers have alot of advantages. When having a closer look at a turn or a maneuver, it involves only one rail at a time, and when the stringer is on the center, all the energy needed to execute a turn, gets dissipated in the effort to flex the whole board due to the stringer and the structure of the board.When high density foam and the stringer are on the rail your energy will have a direct action on the rail you are surfing on, which will occur much sooner and with less effort than a surfboard with a stringer on the center.
Result, better and effortless Surfing.