The gamma zo verve 125mm tennis string set is 122m 40ft long and ensures maximum power and greater spin for deeper shots from anywhere on the court it is ideal for hard hitters and offers an amazing combination of ultra high molecular weight polyester black providing ultimate durability and spin and the co extruded zo high energy co polyester core red for outstanding elasticity max feel and power the string set has a gauge of 17 125mm and features a blend of stiff and soft materia