Originally designed for cross country skiers as a summer workout alternative where they use their upper body to propel a paddle board across the water. To power the Supski, the user pushes back on two poles which are connected to rotating paddles that slide along tracks embedded in the board. This mechanism provides forward motion, extremely tight turns and even go in reverse. With or without an attachable sliding seat, the user can also sit down and row facing forward. The pole paddles can be removed and the Supski can be used as a regular paddle board. In addition, mounting blocks can slide in the tracks and lock anywhere in place and provide mounts for anchoring accessories like chairs and coolers. There's nothing quite like it. The Supski.