Key takeaways
- An assisted-braking device (ABD) helps the belayer hold a fall, adding friction or pinching the rope.
- It reduces reliance on the belayer's brake-hand grip alone, adding a safety margin.
- Examples: the cam-action Petzl GriGri and passive assisted-braking tubes.
- It assists but doesn't replace proper technique — you still keep a brake hand on the rope.
This is general educational information, not instruction. Belaying is life-critical — learn it hands-on with qualified instruction.
What an assisted-braking device is
An assisted-braking device (ABD) is a belay device that helps the belayer hold a fall by adding extra friction or actively pinching the rope when it’s pulled suddenly — reducing reliance on the brake-hand grip alone. The Petzl GriGri is the best-known example.
How they work
- Active (mechanical): a cam rotates and pinches the rope when pulled suddenly (e.g., the GriGri), locking it.
- Passive: the device’s geometry sharply increases friction, pinching the rope against the carabiner under load.
Both engage on a sudden pull, so correct technique still matters.
Belaying a sport climber working a hard move, the belayer uses a GriGri — when the climber falls unexpectedly, the device’s cam pinches the rope and assists the catch, while the belayer keeps their brake hand on and gives a soft catch.
They assist, not replace
An ABD adds a valuable safety margin but does not replace proper technique: keep your brake hand on at all times, belay attentively, and use the device correctly (overriding the cam can defeat the braking). It’s a backup that assists you — unlike a non-assisted tube like the ATC, which relies entirely on the brake hand.
The bottom line
An assisted-braking device helps you hold a fall by adding friction or pinching the rope when loaded suddenly — a real safety margin over relying on grip alone, with the GriGri the best-known example. But it assists rather than replaces good belaying: keep your brake hand on, stay attentive, and use it correctly. An ABD is a backup, not a substitute for technique.
Frequently asked questions
What is an assisted-braking device?
An assisted-braking device (ABD) is a belay device that helps the belayer catch and hold a fall by adding extra friction or actively pinching the rope when it's loaded suddenly. This reduces how much the catch depends on the belayer's brake-hand grip alone, adding a margin of safety. The Petzl GriGri is the best-known example.
How do assisted-braking devices work?
There are two main types. Active (mechanical) ones, like the GriGri, have a cam that rotates and pinches the rope when it's pulled suddenly, locking it. Passive ones use the device's geometry to dramatically increase friction and pinch the rope against the carabiner when loaded. Both assist the braking, but they engage based on a sudden pull, so the belayer's correct technique still matters.
Do assisted-braking devices replace good belaying?
No. They add a valuable safety margin but do not replace proper technique — you must still keep your brake hand on the rope at all times, belay attentively, and use the device correctly (improper use, like overriding the cam, can defeat the braking). Think of an ABD as a backup that assists you, not as a hands-free or foolproof device.
Sources
- Belay devices & safety — American Alpine Club
- Belaying — UIAA