Hi, my name is Stephan, I’m the founder and CEO of raed and the inventor of the ZAED brake assistant that allows heavier climbers like me to climb with their much lighter girlfriend or other lightweight climbing partners.
In this short video I’d like to point out several very important safety issues for brake assistants. Most of these rules apply to all the existing brake assistants in the market.
How to attach a brake assistant
A brake assistant is attached to the first bolt of a climbing route. When it’s activated the rope drag pulls it upwards and the rope is influenced in a way that creates friction to compensate the weight difference in between climber and belayer.
It is important that the device can move freely in the hanger, so it can activate without disturbing influences.
Always use a locking carabiner
Because the ZAED moves continuously up and down during use, non-locking carabiners carry a real risk of accidentally unclipping — especially when a climber repeatedly falls on a crux. We have documented cases of ZAED brake assistants with straight gate carabiners unclipping under exactly these conditions. Since 2025 we supply the ZAEDs only with a Screwgate or Slider carabiner for this reason. If your device currently uses a straight gate carabiner, please replace it with a locking carabiner before the next use.
Never share a bolt or hanger with another connector
Do not clip the device's carabiner into a bolt or hanger that already holds a Maillon Rapide or another carabiner. When two connectors share a hanger, the load is transferred across an edge rather than through the carabiner's spine — this dramatically reduces the carabiner's breaking strength and can cause failure even at low forces. There are multiple documented cases of damaged and broken carabiners resulting from this. If the hanger is already occupied, clip the device's carabiner directly into the existing connector instead.
Check your balls!
Over the past few months, we have learned of several brake assistant accidents involving the accidental opening of the device upon wall contact, resulting in rope release and, in some cases, ground falls. None of these incidents involved a ZAED.
Inside ZAED the rope is secured by a pushpin with a two-ball locking mechanism. To release the pin, you must simultaneously press the protected button toward the device and pull the pin outward — two 180° opposing actions. This dual-action design prevents accidental release if the device strikes the rock face. Before you start climbing, verify that both locking balls are properly engaged. In all of our extensive testing, a correctly locked pin has never been dislodged by climbing loads, fall forces, or break testing.
If in doubt: Preclip the 2nd bolt
ZAED pro provides first bolt support. No brake assistant can alter the amount of rope paid out in the system though. If the climber is above the first bolt without having clipped a second bolt, a ground fall due to rope length remains possible regardless of the device used. If a fall at the first bolt cannot be safely ruled out, the second bolt must be pre-clipped — either by climbing up an adjacent easier route, or by using a clip stick.
Stay safe and climb hard