Figure 8 devices
The descend eight (Figure 8 device) is a descender / belay device ideal for flat descents and dynamic belaying.
The figure 8 belay device is a piece of metal (usually an aluminum alloy) in the shape of an 8 with one large end and one small end.
This device utilities a large surface area in contact with a climbing rope to provide sufficient friction along with proper technique to be used as a belay device or for rappelling. A figure 8 (sometimes just referred to as an 8) is used in conjunction with a climbing harness and locking carabiner to keep a climber safe and control their descent or one's own descent (when rappelling)
Figure 8s offer a very smooth controlled descent when rappelling and lowering climbers.
- They can be used with nearly any diameter climbing rope and don't get as hot as other friction devices because of their ability to dissipate heat efficiently
- The figure eight can also be used with a doubled rope, which is also possible with a rack but not a bobbin.
The figure eight cannot be removed from the rope without detaching the device from the harness, and so could be accidentally dropped, particularly when tackling a rebelay. They also twist the rope which is a particular problem where a re belay prevents the rope untwisting. They do not provide a convenient means to temporarily lock the descent at a rebelay.