OBrien Black Magic Kneeboard Probably the best family kneeboard on the market, the Black Magic does it all. The Black Magic is the best family kneeboard on the market. Its famous cable-actuated retractable fin system and Aquatic Hook make the Black Magic the perfect board for successfully teaching kids and beginners the finer points of deep-water starts. Its size pairs well with adults and kids alike, and its smooth bottom contouring delivers a super stable and extremely comfortable ride for all