The elastic fiber is mainly spandex, and there are also a small amount of other fibers, such as elastic polyester. Usually spandex has 20D, 30D, 40D, 70D, 105D, 140D specifications, knitted 30 is used more, woven 40D is used more, if the elasticity is better, use 70D. If the dyeing is successful once, then the quality of the spandex is better or the difference is not obvious; if you want to repair the color, the elastic damage of the spandex with good quality will be less. ...