FLAT STRINGS & ITF REGULATIONS

In April 2022, Stefano Manfroi, inventor of flat tennis strings, submitted technical information and photographs of his invention to the International Tennis Federation (ITF) in London, requesting clarification on whether this type of string could be used under ITF regulations.

Following review by the Head of Science and Technical, the ITF Science & Technical Team confirmed in writing:

“If adhering to the ITF regulations, using flat strings is permissible.”

2Line represents a further development of this concept. It features a predominantly flat geometry.

ITF Science & Technical Team — 27 April 2022

OFFICIAL TECHNICAL SPECIFICATIONS

2Line: Anisotropic Geometry

A tennis string featuring an anisotropic cross-section with differentiated surfaces, designed to promote snapback and ball rotation.

2.4 mm

Cross-Section Width

~0.7 mm

Cross-Section Thickness

>70 kg

Breaking Load

20-25 kg

Recommended Stringing Tension

TECHNICAL DATA

Physical Specifications

2.4 mm

Nominal Width

~0.7 mm

Approximate Thickness

>70 kg

Breaking Load

20-25 kg

Recommended Stringing Tension

MATERIAL CHARACTERISTICS

2Line String Properties

2Line is a highly resistant tennis string with very low elongation, designed to maintain stringing tension over time.

Tension Stability

Very Low Elongation

High Resistance

2Line maintains stringing tension over time, helping preserve consistent string-bed characteristics during use.

2Line features very low elongation, one of the defining mechanical characteristics of the string.

Despite its reduced thickness of approximately 0.7 mm, 2Line has a breaking load of over 70 kg.

Compatibility Guide

Check Racket Compatibility

With its 2.4 mm width, 2Line can be strung on numerous current racket models, thanks to the wider grommet openings adopted in recent years by manufacturers such as HEAD, Wilson and others.