String set, main string, and cross string

Abstract

A string set is a string set strung on a racket as a main string and a cross string, and is configured to include a first string strung as any one of the main string and the cross string and has a small friction force and a small diameter and a second string strung as another one of the main string and the cross string and has a larger friction force and a larger diameter than the diameter and the surface friction force of the first string. This distributes functions to the first string and the second string to obtain both the hairpin performance, which is improved by the large surface friction force and outer diameter of the string, and the cut smash performance, which is improved by the small surface friction force and outer diameter of the string, at the same time.

Dependencies are inferred from the claim text.