R-N-R, Heavy Duty Twin Loop Runners Twin loop runners are a multi-purpose tool. They may be used as anchor slings, hose grab tools, to secure smoke ejectors, as stirrups in personal ascending systems, to drag equipment, to secure ladders and as a tether between rescuer and victim. HDTL heavy duty runners are made of 1" (25 mm) solid nylon 6,000 lb. (2,722 kg.) webbing. All runners are sewn with nylon thread. Weight will vary with length. Figure 1 oz. (28 g) per foot of finished length. Made in the U.S.A.