Irukandji is a very special rounded/rectangular polyester string. It is soft and provides great snap-back and feel. It enhances spin potential due to its added elasticity. It was engineered to function as the ideal Cross string. Its smooth surface allows the mains and crosses to slide on each other, minimizing notching and maximizing snap-back, which increases spin potential. With remarkable feel and comfort, it bridges the gap between co-poly and multi filament strings. Performs well in full bed, but is highly recommended as a Cross-string with Multi or Natural Gut in the Mains. Available in Grey. Diameter: 0.90 x 1.45 mm Individual 12m Set Recommended tension: - Normal poly stringing tension when used as full bed or as a Cross in a hybrid. Note: Given Irukandji's unique shape, it is officially rated at 0.90 x 1.45 mm in diameter, which is comparable to a 17g round string. Stringing Tips: Irukandji will tend to lay against the gut or multi main on its larger surface area, flat side. Don't worry if this does not happen every time, and you see a turn or two throughout stringing. It will not be a problem.