A trade name for polyester round sling. Used extensively for suspending truss in portable applications. Commonly used in 3', 4', 6', and 9' lengths. While the name is attributed to SpanSet, products from Lift-All are likely the most widely used in the entertainment industry, along with a few others. If the polyester round-sling contains wire rope inside, it is usually called Gac Flex™, or Steel-Flex--again both brand names and not necessarily the manufacturer.