1) 20D spandex is covered by 30D/12F nylon Dty 2) Available for sweaters, knitting fabric, silk fabric We can produce spandex covered yarn , they are available for socks, knitting fabric, underwear ,sweaters.Main specification:20/30 20/40 20/70 30/70 40/70 20D/30D/12F Spandex Covered Nylon Yarn