Thefigure 8belay device is a piece of metal (usually analuminum alloy) in the shape of an 8 with one large end and one small end.
This device utilizes a large surface area in contact with a climbing rope to provide sufficient friction along with the proper technique to be used as abelay device or forrappelling. A figure 8 (sometimes just referred to as an 8) is used in conjunction with aclimbing harness and lockingcarabiner to control a belayed climber's descent, or one's own descent when rappelling.
Figure-eights offer a smooth controlled descent when rappelling and lowering climbers.[1] They can be used with nearly any diameterclimbing rope and don't get as hot as other friction devices because of their ability to dissipate heat efficiently.[2] 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 rebelay prevents the rope from untwisting. They do not provide a convenient means to temporarily lock the descent at a rebelay.
