Single-core single-layer fiber tennis string is the most popular nylon string section structure today - most "gut string" are single-core single-layer fiber structure. The biggest advantage of this kind of string is that the pounds are not easy to decay, and the "crisp" feel of hitting the ball is close to the natural gut string. The texture and thickness of nylon inner core and outer fiber will affect the hitting feeling and comfort of the tennis line.

The complex string structure mentioned in the tennis string refers not to the section structure of the tennis string, but to the string-through structure. Usually, the stronger string is worn on the vertical string, and then the nylon string or natural gut string with good feeling is worn on the horizontal string. This string-through structure is not only durable, but also has good ball feeling.