How to distinguish nylon from polyester when buying a bagPolyester is also known as POLYESTER, and China is named polyester. The characteristics are good air permeability and moisture wicking. It also has strong acid and alkali resistance and anti-ultraviolet ability. Generally, fabrics with multiples of 75D are polyester, such as 75D, 150D, 300D, 600D, 1200D, and 1800D are all polyester, and the fabric is darker and rougher than nylon. D is an abbreviation for DENIER, and the higher the number of D, the greater the density and thicker the material.