It is a numerical value given to determine the size (thinness, thickness) used for the identification of the yarns.

The samples that are taken from the companies that produce yarn around the world are tested in the laboratories by the Uster Company. After testing the samples, the results are turned into statisctics.

It is produced from the long fibers of cotton. Ring yarn is divided into two as carded and combed.
Combed Yarn is a yarn that has been combed and produced from cotton fiber of long and fine quality.
Carded Yarn is also produced from fine quality cotton fiber and they are not combed.
Open-end Yarn has completely different production technique compared to ring yarns. Unlike ring yarn, it is produced from cotton’s short fibers.