The famous cable-actuated retractable fin system and the aquatic hook make the Black Magic the prfect board for teaching kids and new riders the finer points of deep water starts. The O'Brien Black Magic is the best all-around family kneeboard on the water and has a smooth bottom contour that makes it super stable and extremely comfortable while riding. The board's super low profile and twin-tip shape provide awesome speed and performance. The power control knee pad and 3" padded strap keep you locked in tight. The Black Magic Kneeboard is rotomolded with a durable plastic base. 52"L x 21-3/4"W.