A belay rappel device is a rounded piece of steel or aluminum witch adds bends in a rope. This allows an increase of friction. The outcome is control of the amount of rope passing through the device in an ascending or descending orientation. Often in the shape of a figure of eight or tube.
Common rock climbing and canyoneering uses:
- Rappelling
- Belaying
- Rope ascension
Here are a few examples of different styles of belay/rappel devices