Traditional climbing equipment- ascenders

Traditional climbing equipment- ascenders

An ascender is a mechanical rope-climbing tool designed to help you scale steep or difficult ground on a fixed rope. Here's what to use them for, and how.

An ascender is a mechanical rope-climbing tool designed to help you scale steep or difficult ground on a fixed rope. In climbing they are primarily used on major routes where ropes will be fixed in place in order to retreat back to the ground or to safeguard difficult sections (siege style and expeditions), or when the second(s) wish to follow the leader quickly and easily (big wall). Generally speaking, ascender types are either 'standard' or 'emergency'.


These usually work via a toothed cam that grips the rope, allowing it to slide up the rope but not down

Standard ascenders

These usually work via a toothed cam that grips the rope, allowing it to slide up the rope but not down. They are placed onto the rope, and feature a safety trigger designed keep the rope from coming astray from the cam. 

Handled and unhandled models exist. Most manufacturers make the handled models in both left handed and right-handed versions. The unhandled ascender is usually clipped to the harness and held in place by a chest harness in order to keep it in position. Two ascenders are usually required for all but the lowest angle climbs.

Emergency ascenders

These are either minimalist cam designs, where a tiny cam is held between two small plates and is locked onto the rope via a screwgate, or a single grooved cleat, which traps the rope and has no moving parts. These units are generally used for super lightweight ascents where jumaring will be limited, or for big routes where an emergency may require them for self-rescue (these devices a far easier to use and more reliable than a Prusik loop).

These devices a far easier to use and more reliable than a Prusik loop

Ascenders are usually attached to the harness either directly (unhandled and emergency designs) or via a sling. A foot loop (or aider) is clipped to one or both of the ascenders and you use your legs to move up the rope rather than using your arms. An ascender can be used to descend by pushing the cam away from the rope and pulling the ascender down but more often it is much faster just to set up a descender and abseil.

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