No best answer

Polyester fiber, commonly known as "polyester". It is a synthetic fiber obtained by spinning polyester formed by polycondensation of organic dibasic acid and diol, referred to as PET fiber, which belongs to high molecular compound. Invented in 1941, it is currently the largest variety of synthetic fibers. The biggest advantage of polyester fiber is that it has good wrinkle resistance and shape retention, and has high strength and elastic recovery ability. It is durable, anti-wrinkle, non-ironing, and non-sticky.
Polyester fiber is abbreviated as pet fiber, and the two are the same to a certain extent.