Why doesn't the climbing splay descent control device use steel?

Because the figure-eight ring is used as a protective device, it mainly relies on the friction between the rope and the figure-eight ring to achieve the effect of low braking force. If the figure-eight ring is made of steel, the power rope will wear out because it is made of nylon. Steel is too hard when rubbed. Compared with the price of a rope, the figure-eight ring is much cheaper, so I chose aluminum, so I wore the figure-eight ring. Replace the 8-ring instead of changing the rope frequently. Do you understand what this means? If you still don't understand, you can Baidu "Langma Rock Climbing Equipment"