S number (wool)

An S number on the label of wool suits or other tailored apparel, wool fabric, or yarn, indicates the fineness of the wool fiber used in the making of the apparel, as measured by its maximum diameter in micrometres. Fiber fineness is one of the factors determining the quality and performance of a wool product. In recent years it has also become an important marketing device used by many mills, garment makers, and retailers. The S number appears as a plural with an s or 's following the number, such as 100s or 100's.


An S number on the label of wool suits or other tailored apparel, wool fabric, or yarn, indicates the fineness of the wool fiber used in the making of the apparel, as measured by its maximum diameter in micrometres. Fiber fineness is one of the factors determining the quality and performance of a wool product. In recent years it has also become an important marketing device used by many mills, garment makers, and retailers. The S number appears as a plural with an s or 's following the number, such as 100s or 100's.
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