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 performance of single-core multi-layer fiber tennis wire is similar to that of single-core single-layer fiber tennis wire, but its durability and ball eating performance are better.