6006.31.00.40 - Of polyester (222)

This HTS category, 6006.31.00.40, specifically covers knitted or crocheted fabrics of polyester that are unbleached or bleached, and of a double knit or interlock construction. These fabrics are characterized by their synthetic fiber composition and the specific knitting structure, which results in a fabric that is typically reversible and has a dense, stable appearance with no distinct right or wrong side. Examples include polyester interlock and double knit fabrics used in apparel such as activewear, loungewear, and linings.

This classification is distinguished from its siblings by the specific fiber content. While siblings 6006.31.00.20 cover similar fabrics made of nylon, and 6006.31.00.60 encompasses other synthetic fibers under this construction type, this particular subheading is exclusively for polyester. The "unbleached or bleached" designation indicates that the fabric has not undergone dyeing or printing processes, maintaining its natural color or having been whitened.

As this is a leaf node within the HTS, there are no further subcategories. Classification decisions at this level rely heavily on confirming the material composition as polyester and verifying the double knit or interlock construction. The absence of further subdivisions means that all unbleached or bleached polyester double knit or interlock fabrics will fall under this specific code, provided they meet the other definitional criteria of Chapter 60.