The degree of traction delivered by a wakeboard is largely dictated by the number of fins under the board, which serve to grip the water and allow for tighter control. Some fins are fixed and are best suited for open water, while others can be removed to let you handle both boat riding and cable parks. Boards also use channels—either in addition to or instead of fins—that also improve tracking, though boards with only channels don’t track as well and are best used in park riding.