Sewn eye & eye Prusik of Ocean Poly, 8mm X 28″, 23kN (5,175 lb.) breaking strrength. The strength of Ocean Polyester comes from the core, and for tree care, the Treemagineers have introduced a Polyester kern because of its high abrasion resistance, tolerance of flexing and high wet strength. This is an excellent hitch cord for the professional tree climber.