4G features maximum tension and a cushioned feel on impact, lending itself to excellent playability and adaptability to the modern game defined by power and spin. Boasting the elements of a control string minus the tension loss and discomfort of early polyester strings, 4G sets the standard for players craving precision. Used by many tour players, including the Williams sisters and Grigor Dimitrov. 100% Solar Power is an initiative that uses solar panels as the main energy supply to promote a sustainable, clean environment Molecular chains strategically aligned to maximize tension maintenance Provides the most control from the polyester string families Polyester string that features maximum tension and cushioned feel on impact Composed of a materials that increases strength and flexibility of the string Each set is individually numbered for quality assurance