Babolat RPM Rough is the textured version of RPM Blast, one of the most popular co-polyester ever made. The standard RPM Blast, this string is a co-polymer monofilament with an octagonal shape and a special cross-linked silicone coating. RPM Blast Rough is perfect for aggressive players who like to attack the ball with long, fast strokes. Our play testers found it a tad softer and more powerful than the original RPM Blast, resulting in a slightly more penetrating shot.