Taffeta is a crisp, smooth, plain-woven fabric with a close weave and slight sheen. It is made of various fibers, such as silk, rayon, or nylon, and often used as lining for apparel and sleeping bags because of its resistance to penetration by down. 1.3 oz. (ounces per square yard of fabric) is ultra-light, luxuriously soft taffeta lining ideal for next to the skin use. 2.6 oz. nylon is a tightly woven fabric used for tent flies to provide protection from the elements.