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Back-up
A device that is used to provide a secondary (ideally handsfree) safety system to provide a fail safe, if the primary means of ascent or descent fails. Some devices, like the Singing Rock Back-Up / Rocker, use a rotational braking system to bend the rope and prevent it from moving any further through the device. Petzl’s Asap however, uses a clever centrifugal system that pinches the rope and blocks rotation of the toothed wheel, stopping any movement instantly. In most instances, these Rope Back-Up devices should be used in conjunction with an energy absorbing lanyard.
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