48nm yarn is the specification description of the yarn, where the number 48 represents the fiber diameter or linear density of the yarn, and the unit is nanometer (nm). Yarn is composed of fiber, and the diameter of fiber is one of the important factors that determine the thickness of yarn. The fiber diameter of 48nm yarn is very fine, and it is usually used to make high-quality textiles, such as high-grade clothes, curtains, carpets and so on.

It should be noted that the specification of yarn includes not only the fiber diameter, but also other parameters such as yarn twist, count and number of strands.