Fast Back Cobalt Head Rope Team Ropes Tagged "4 Strand Heel" Fast Back Ropes Fast Back Cobalt Heel Rope Fast Back Ropes Quick Release Team Ropes tagged "4 Strand Heel" Fast Back Ropes. The Fast Back Cobalt 35' Heel Rope is a perfect combination of poly and dyed nylon resulting in a highly durable rope. The Cobalt is medium in diameter and weight and will likely appeal to ropers who prefer more tip weight and less body or bounce.