Black Knight Great White Doubles Squash Racquets : The Black Knight Great White Doubles squash racquet is part of the John White Series. Players will enjoy a highly maneuverable frame with a large sweet spot for fast and powerful hitting. The Supernick ZX string helps apply a nice spin on the ball with the benefit of excellent durability. Features Power of 6 style that includes tuning at 6 key stress points to reduce overall weight and prevent damage. Thermal Core Technology provides a stronger frame without irregularities, ensuring better durability. Nano Crystaline Technology is part of a graphite frame to provide a balanced frame. Endorsed by professional squash player John White.