Tightly braided nylon fibers give this sleeving excellent abrasion resistance. As it wears, the fibers frizz and make the outer wall thicker for improved protection. The interior is smooth to reduce snags during installation. It meets Mine Safety and Health Administration (MSHA) standards for fire protection in mines. Because this sleeving is non-expandable, it does not stretch, so it’s best for applications where you know the exact diameter of the items you need to protect.