XRT means Extreme Rope Technology and is simple and easy to use. This patented device uses specially designed ribs to lock the rope inside the wheel Hub and is easily tightened with one hand. The ratchet feature on the wheelset locks the rope and prevents unwanted tensionloss. A simple thumb operated release trigger disengages the ratchet lock to unwind when you desire. Precision injection molded housing resists corrosion in extreme weather conditions.