Between comfort and flexibility, the Babolat RPM Soft 17 1.25 gives the best of both worlds. It's constructed with three layers: a flexible polyamide core to cushion impact, aramid powder within the co-polyamide middle layer for durability, and an outer layer containing silicone to facilitate string movement. If heavy topspin and reliable control are your goals, go with the Babolat RPM Soft 17 1.25! Outer layer in co-polyamide and silicone facilitates string movement for spin. Middle layer in co-polyamide and aramid powder enhances resistance for durability. Inner layer in polyamide is very flexible and comfortable. Easier for stringers to install than traditional co-polyester Who's it for? Young competitive players searching for the right balance between comfort and durability. Competitive players who've played with poly strings and want something softer. Intermediate players who want to use a monofilament like the pros. String breakers who need more durability than a multifilament.