Not so good. The quality of 30 yuan ice silk vest is not good. Because a penny is worth a penny, the quality of a piece made of 30 yuan is definitely not very good. Ice silk is the trade name of a chemical fiber. Ice silk is also called rayon, viscose fiber and viscose filament. Specifically, it is modified viscose fiber. This kind of fiber has better hygroscopicity and breathability than ordinary viscose fiber, and also has better shape retention and drape.