The feather and down filling material is long in the abdomen of geese and ducks, and it is a flower-like fluff of a reed, which is called a feather. Because down is an animal protein fiber, the down-ball fiber is densely packed with thousands of triangular pores, which can shrink and expand with temperature changes, and produce a temperature-regulating function, which can absorb the hot air flowing from the human body and isolate the cold air from invading. . From the detection of fluffiness, the down is higher than the warm materials such as silk and cotton. For example, the minimum standard of 450 degrees fluffy 90 duck down is better than silk and cotton fluffy, so the feather is pure as a warm material, it The economic value is much higher than other warm materials