A figure eight with ears
One method of rigging a figure eight
One method of tying off a figure eight
These are probably the most common descenders as they are widely used by commercial groups. They are cheap and reasonably easy to use. They are not ideal in wet canyoning situations as they take some time to get on and off the rope, and can easily be dropped into pools etc when hands are cold.
The basic figure eight consists of a piece of metal with two holes, coincidentally shaped like the figure 8. The rope generally runs through the large hole, and over the knob formed around the small hole. The small hole is then clipped into the carabiner on the harness.
Some figure eights have 'ears'. These are to stop the rope being pulled over the large hole, and forming a girth hitch.
|Safe||The main risk with 8s is if the 8 is not sitting correctly on the carabiner at the start of descent. This can result in cross-loading or twisting of the gate, potentially breaking the carabiner, and deaths have occurred.|
|Variable speed||Yes - you can rig the 8 in a number of different configurations for varying speeds.|
|Variable speed during descent||No|
|Easy to lock off||Not particularly|
|Rescue use||Varies, usually depending on the size of the 8. Some larger 8s are designed for rescue use.|
|Heat dissipation||Average to good, depending on size.|