RPM Blast Gauge 17Famously used by Rafael Nadal, Babolat RPM blast is an octagonal polyester with massive spin potential and snap back to elevate your game. Since Nadal's success with this string, many other players have made a switch to this string due to its soft. er feel than other polyester strings. While softer, RPM Blast is not overly powerful which lets players using +11 ounce racquets and powerful strokes swing with confidence. Control is very reliable and