The use of a belay device has made climbing much safer. There are many devices, each with strengths and features that are advantageous for different types of climbing environments. Several devices have the capability to serve as both belay and rappel devices. Belay devices operate by allowing rope to be freely give to the climber when needed, or by allowing the belayer to immediately apply friction, or lock, the rope when necessary. A belay system requires a belay device, harness, anchor, rope and belayer-climber team. The belayer stands at the bottom of the climb. As the climber moves the belayer must pay out rope through the belay device and be ready to catch a fall at any time. When/if the climber reaches the finish the belayer engages the belay device so it causes friction with the rope.
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