Master rigger Mike Parnell walks up to a rack and picks up what looks like a giant rubber band. In reality, it is a 10-ft-long, 2-in.-wide lifting sling made of thin, yellow nylon webbing. Parnell ...

...material for the application,” says Parnell. He adds that the movement between synthetic slings and fabricated steel can be “deadly.” Softeners, or edge protectors, can keep a sling from rubbing ...