The world's most in-depth and scientific reviews of outdoor gear

How We Tested Belay Devices

Sunday April 28, 2019

This review is based on months of testing with 15 of today's most popular belay devices, but it rests on a 10-year foundation that goes back to 2009 when we first started examining the product category. While the belay device market has changed considerably in that time, the results haven't so much: the GriGri (with updates) remains our favorite, and the ATC Guide and Reverso keep fighting for second place.

Some of the original pieces we tested for this review circa 2009.
Some of the original pieces we tested for this review circa 2009.

Four different climbers have played the role of lead reviewer of belay devices over that time, and it is remarkable how little variance they have found in their testing. This isn't a case of advertising dollars holding sway either. All the belay devices tested were purchased by OutdoorGearLab on the retail market, and the reviewers had no financial incentive to score any product over another. Our conclusions are based entirely on our interactions with these devices. We sought out opinions from friends and acquaintances, but anything we couldn't prove ourselves we either left out or mentioned the source. Here's how we specifically tested each model for our various comparison metrics.

A selection of the belay devices we have tested on the edge of the basalt cliffs in Smith Rock State Park  where we did much of the testing for the latest round  and here rappelled over the edge repeatedly to understand how each performed.
A selection of the belay devices we have tested on the edge of the basalt cliffs in Smith Rock State Park, where we did much of the testing for the latest round, and here rappelled over the edge repeatedly to understand how each performed.

Catch/Bite


Taking some falls to test the bite of different belay devices.
Taking some falls to test the bite of different belay devices.
By climbing with each device regularly we got a good sense of how quickly and strongly each one engaged when a climber fell or took on the rope. We used skinny 9mm lines and thicker workhorse ropes in the 9.7-10.2mm range to see if there was a performance difference and also compared how hard we had to hold down on the brake hand to hold the weight of the climber. We also scoured the climbing literature and reported on some interesting tests by the German Alpine Club that compared the relative braking strengths and device engagement for various assisted braking devices. With the increasing popularity of passive assisted devices, and some manufacturer claims that they perform as well as an active device, it was interesting to see some lab tests that compared their effectiveness and showed their weaknesses.

Lowering/Rappelling


We rappelled and lowered with each device dozens of times, and would switch devices between routes to get that side-by-side comparison of how smooth they felt relative to each other.

Rappelling a single line as a test to see how this device performed. We set up this line near a convenient scramble back to the top of the cliff so we could lap it over and over and over  using a different device each time to easily compare their relative merits and issues.
Rappelling a single line as a test to see how this device performed. We set up this line near a convenient scramble back to the top of the cliff so we could lap it over and over and over, using a different device each time to easily compare their relative merits and issues.

Feeding Slack


For this category, we noted the smoothness of the pull and the complexity of the belay technique. We tried to keep an open mind with each device and not judge it by our first use, but rather how it felt after multiple days spent using it and practicing the proper technique. We should note though, that due to the ubiquity and popularity of the Petzl GriGri for the last twenty-plus years, most of our testers have been using that device exclusively except when multi-pitch climbing; it was "interesting" for them to try out new belay techniques again!

Belaying with a GriGri. After years with the same device  switching to a new technique wasn't always easy. Many partners got short-roped as we learned the ins and outs of each model. Sorry!
Belaying with a GriGri. After years with the same device, switching to a new technique wasn't always easy. Many partners got short-roped as we learned the ins and outs of each model. Sorry!

Auto Block


The hanging scale set up we used to conduct our Auto-Block resistance test.
The hanging scale set up we used to conduct our Auto-Block resistance test.
While we tested the auto block devices on multi-pitch routes, we also conducted an auto-block resistance test indoors. For this experiment, we set up each device in auto-block mode on a hanging scale. Then we pulled 10 meters of slack rope through while recording the weight on the tared scale. The actual number measured wasn't significant. Instead, the relative difference between devices is what we focused on. All devices were in brand new condition, and we used the same Petzl Attache carabiner every time. The results were surprising, demonstrating how much resistance some devices actually add. We encourage you to play around with your equipment because your preferred rope or belay biner could give you different results. We also noticed that wear could have a big impact—a worn out ATC Guide gave 15-20% less friction than a new one.

The results of our auto block test  where we attached each device in auto block mode to the hanging scale and pulled 30 feet of slack through  seeing how much resistance in pounds there was for each one. Tested with a 9.5mm rope. The numbers are not very important  rather the relative differences are what we are trying to show.
The results of our auto block test, where we attached each device in auto block mode to the hanging scale and pulled 30 feet of slack through, seeing how much resistance in pounds there was for each one. Tested with a 9.5mm rope. The numbers are not very important, rather the relative differences are what we are trying to show.

Weight and Bulk


This was likely one of the least "subjective" metrics in our testing process, as the scales don't lie! We weighed each model on our digital scale and also considered how large the unit was. Some results were surprising. We thought the Mad Rock Lifeguard would be significantly lighter than the GriGri since it's so small, but it's 5.4 ounces isn't that much weight savings over the 6.3 ounce GriGri and 7.1 ounce GriGri+.

The Mad Rock Lifeguard (right) is certainly more compact than the Petzl GriGri+ (left) but it's only 1.7 ounces lighter.
The Mad Rock Lifeguard (right) is certainly more compact than the Petzl GriGri+ (left) but it's only 1.7 ounces lighter.

In the end, the right belay device for you is whichever one keeps you safe. You may disagree with the final standings, but we hope you found our analysis informative.