What is an ABD?


Note: In Feb 2017, we organized a series of ABD workshops to educate people about different ABDs and talk about their advantages and disadvantages. This post is based on the content shared during that workshop.

What is an Assisted Braking Device (ABD)?

Traditional belay devices use friction to assist you in managing the weight of your climber when you need to catch a fall. Examples of these include tubular devices such as the Black Diamond ATC, or the Petzl Reverso.

Assisted belay devices take this one step further and assist in holding a falling or hanging climber. 

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Classification of ABDs 

Active ABDS

  • Assisted braking relies on pinching mechanisms within the device

  • Have moving parts within the device

  • Independent of the position of the brake hand

  • E.g. Petzl Grigri, Madrock Lifeguard, Camp Matik, Trango Cinch, Edelrid Eddy

Passive ABDs

  • Assisted braking effect is due to pinching of rope between the carabiner and the device

  • Triggered by a slight pull of the rope and is generally dependent on the type of carabiner used

  • Only works if brake rope in a specific direction (brake hand in brake position): This means that if you let go of your brake hand during a fall, the device may not brake

  • E.g Edelrid Megajul, Mammut Smart, ClimbTech Click-up

Why ABDs?


  • Active ABDs might help to arrest fall even if belayer gets knocked unconscious

  • Minimizes incidents from climber letting go of rope due to rope burns or not being able to catch full force of fall


  • More complex device to learn especially for feeding rope (lead climbing) and lowering

  • Risk of uncontrolled lowering if climber is not proficient in use of device

  • More costly compared to most friction-based devices

How to use an ABD?

For a proficient belayer, using an ABD is not that much different from using a tubular device. 

Some basic things to look out for, especially when lead belaying:

  1. Setting Up the Device – Follow the diagrams on the device to guide you. Do a tug check by pulling fast on the climber end to check that it catches

  2. Feeding Rope – Feed consistently and let the hand on the climber end of the rope lead the way. Avoid fast movements as the ABDs might lock. And always always remember to keep one hand firmly on the brake position in braking position.

  3. Taking In – The usual 5-step belay is sufficient.

  4. Arresting a fall – Give a dynamic belay by moving in a controlled manner in the direction of the pull from the fall.

  5. Lowering – Varies from device to device. Please refer to manufacturer recommendation. Generally, always keep your master hand on the braking rope.

‍New devices are coming to market on a regular basis. If using a new device or if in doubt, always check out the manufacturer recommendations and/or seek professional guidance.

Choosing a device 

Some factors to consider…

  • Where will you be using the device? 

  • How much are you willing to spend? Remember that expensive doesn't mean better though.

  • Ease of Feeding / Ease of Lowering / Handling Errors. This may be a little bit subjective so it's best to try out the device for yourself before committing.

Check out this useful comparison table for some of the more common devices: http://www.alpenverein.de/chameleon/public/33836d33-9b6d-2389-4802-7115db2dfb12/assisted_braking_devices_chart_26375.pdf 

‍Whatever device you choose, smooth handling is definitely something that comes with familiarity and practice. And of course, no device is a substitute for bad belaying! 


  • http://www.alpenverein.de/chameleon/public/450e9f1b-9c38-a0e9-725d-c88dd8c4cdb1/Belay_Device_Recommendation_26255.pdf

  • http://www.climbing.com/gear/catch-this-a-close-look-at-assisted-braking-belay-devices/

  • http://www.alpenverein.de/chameleon/public/d2a81975-4acc-1e56-48b9-53b166da2233/assisted-braking-belay-devices-advantages-disadvantages-differences_26374.pdf