The Gamma Stinger Hybrid 1.30mm tennis string set features a main gauge of 16 (1.30mm) & a cross gauge of 17 (1.27mm). The string set offers Dynalon centre core & outerwraps with Nylon 6 coating, as well as Copolymer polyester monofilament. Synthetic cross string provides great playability, whereas durable polyester main string ensures extra string life.