Babolat RPM Blast 16 is the new string used by Andy Roddick and Rafael Nadal. An excellent choice for big hitters looking for extra spin. Octagonal (8-sided) cross-section adds the extra bite on the ball for added topspin and slice. New high density co-polymer polyester (PET) monofilament combined with a new cross-linked silicone coating provides even more spin and greater ball control. Color: Black Gauge: 16g Mini Reel (330 ft/100m) Babolat Tennis String 242101-16