The Luxilon 4G Rough 125 is designed to provide much better tension maintenance & comfort than standard monofilament polyester strings. It is textured to help generate enhanced spin & offers increased flex achieved due to surface denting, which results in added power potential. The string has been treated at a molecular level to ensure extra durability & has a 16L (1.25mm) gauge for added playability. It is supplied as a 12.2m (40ft) set that enables you to re-string one racket.