are produced by wrapping two strands of a non-elastic covering yarn, such as nylon and/or polyester, in opposite directions around an elastic spandex or rubber core. These yarns are used primarily for socks, narrows, medical products, sheer hosiery and apparel.

are produced by wrapping a single strand of nylon or polyester around an elastic spandex or rubber core. These yarns are used primarily for women's hosiery, narrow fabrics and seamless apparel.

are produced by a high-speed process that entangles spandex, nylon or polyester with air to produce an elastic yarn. These yarns are used in socks, tights, and woven apparel.