The Wilson NXT Tour 16 tennis string, supplied here as a 12.2m (40ft) set, feels very much like natural gut & provides the biggest sweetspot of all Wilson NXT strings. Its ranked number 1 for playability & comfort by USRSA string surveys. 1120 High Crystallinity Xycro micro fibres are impregnated with 48% Polyurethane, which results in additional shock dampening. The gauge of the string is 16g (1.30mm).