BeYarns elastic covered yarn is spandex yarn wrapping with one or two strands of filament yarns to increase filament yarns with higher elasticity and construct textile fabrics for better draping property and keeping in shape. A:Single Covered Yarn-SCY Spandex is wrapped with one filament yarn such as nylon. It can be divided into two specifications- S and Z twist. It is commonly used Z twist in elastic fabric, but socks and underwear use both S and Z twist to body curve. B:Double Covered Yarn-DCY Spandex is wrapped with two filament yarns in opposite directions. One is outer covering, and the other is inner covering. The different TPM makes various sense of comfort touch. Use: Tights, Woven fabrics, Flat knitting, Narrow fabrics, Circular knitting.