Set of 2 Dual Planer Boards are used in conjunction with a mast system. They are ballasted so the nose is slightly raised to cut through the waves easier and have a three position tow point to allow you to adapt to different water conditions instantly. To store, simply fold the outside board forward. Each board can be used on either port or starboard and comes with a sample OR-10 Adjustable Light Tension Planer Board Release. Your planer board has 3 tow point positions that can be used by moving the split ring. The towline height off of the water and the distance away from the boat will determine which position will work the best on your boat. Normally the front hole is for higher speeds (3+ mph), the middle hole is for normal speeds (1.5 to 3 mph), and the back hole is reserved for slow speeds (under 1.5 mph). It is MANDATORY that a split ring be used. Without the split ring, it is possible to jam a snap swivel on the tow arm, causing the board to dive. Dual planer boards are NOT designed to be used with full diving planes. Each one measures: 28-1/2"L x 7-3/4"D x 8-3/4"W.