Yale Ultrex is a 12-Strand Single Braid of 100% Ultra High Molecular Weight Polyethylene (UHMPE) fiber enhanced with Yale's Maxi-jacket HP coating supplying superior abrasion resistance. ultrex's braid angles and twist level are designed to optimize break strength and keep stretch low. UHMPE is the most forgiving high modulus fiber, giving better sheave cycling capabilities than other high tech fibers. Ultrex has zero water absorption and maintains its flexibility even in freezing conditions.