What is the best-locking carabiner for rock climbing? We compared 15 of the best-locking carabiners in various tests to find out. We’re positive that the Petzl Attache still is the best-locking carabiner in the market.
We judged each carabiner on the following six categories: lightness/compactness, ease of unlocking, gate hang-up, amount of knots held, rope pull smoothness, and gate clearance. In the end, we found that no one product excels at everything. Instead, three main categories had their top products: lightweight locking carabiners, medium belay, and rappel carabiners, and large belay and rappel carabiners.
Read below to understand our picks.
Best Overall Locking Carabiner: Petzl Attache
Our choice goes to the Petzl Attache. It was the only carabiner to score high in every category and the only light carabiner to really excel in the overall scores. This carabiner excels at just about everything. Its main drawback is the price.
Best Value: Black Diamond RockLock
The Best Value goes to the Black Diamond RockLock, which scored very well in most categories except for being light and compact. It was not only a top scorer but also among the cheapest carabiners at $10-12. We also have a Great Value award to the Mad Rock Super Tech Keylock Screw, which is the carabiner we would load up on if we were on a budget.
Best Lightweight: Mad Rock Super Tech Keylock Screw
The Mad Rock Super Tech was our favorite ultralight biner. Since we are obsessed on all things light, we would probably just buy these and the Petzl Attache if we had an unlimited budget.
Best for Belaying: Edelrid HMS Bulletproof Triple FG
Whether you use an ATC or a gri-gri for belaying your climbing partner, it needs to be connected to your body or the anchor using a locking carabiner. Most gear manufacturers design lockers with belaying in mind that have features such as an auto-locking gate and keep the belay device-oriented correctly. The best of these is the Edelrid HMS Bulletproof Triple FG, winning our Top Pick award for best belay locker. The gate is auto-locking, so if it is closed, it is locked, no matter what, but it also requires three actions to unlock it, ensuring the most secure connection possible. We love the stainless steel insert that covers the basket where the most wear takes place, ensuring this ‘biner will last a long time. In our testing, the internal spring bar is the most effective way to orient the ‘biner in the direction it needs at all times without risking cross-loading or flipping upside down.
How We Chose
Lightness and compactness
Our favorite lightweight locking carabiner was the Mad Rock Super Tech which edged ahead of the other two super light carabiners: the Wild Country Ascent HMS and the Trango SuperFly Screwlock.
Which was the lightest?
It’s hard to say because the manufacturer’s weight listings were a little different than our own measurements. They are all within a few grams of each other with the Trango being a little lighter than the Mad Rock. The Mad Rock is our top pick because it had the smoothest keylock gate, was really easy to handle and just looks cool. If we were on a budget, we would go with Mad Rock as our main choice. The Trango is a solid biner but we prefer the keylock gate of the other biners. It was also the most expensive of the three.
Another notable light biner is the Petzl Attache, which is not as light as these three but is probably the lightest considering its size. With most light biners, the small size means you sacrifice a little in the range of activities the carabiner is good for. That is why the light biners, in general, score lower. They just don’t do a lot of functions as well as bigger locking carabiners. The Petzl Attache, on the other hand, is very light and functional across various tasks.
Ease of Unlocking and Locking
The DMM Boa Quicklock was the easiest carabiner to lock and unlock. The twist lock is incredibly smooth, and the carabiner’s shape makes it very easy to lock and unlock. In general, all the twist-lock carabiners were easier to lock and unlock than the screw gates. As far as screw-gate carabiners, there were five carabiners that all tied for best. The Petzl carabiners stood out for having bigger twist gates that were easy to use, especially with gloves. The DMM Boa Quicklock stood out for taking just one accurately placed twist to completely unlock (this probably only works with the carabiner is new and smooth).
Gate Hang Up
All the keylock carabiners did great in these tests which involved seeing how easily the gates got hung up on bolt hangers and slings with unclipping. It’s hard to single out a clear winner in this category. The clear low scorers were the non-keylock carabiners. We would still use a non-keylock carabiner, but we really prefer the keylock feature.
Number of Knots Held
The DMM Boa and Black Diamond Rocklock scored top for holding the most knots and slings. These are great locking carabiners to use as the “master point” of an anchor because you can easily clip multiple knots on a bite, slings and other items. The Petzl carabiners and the Black Diamond Mini Pearabiner also scored very high. Not surprisingly, the worst scores came from the lightest and smallest carabiners. The exception was the Petzl Attache 3D which is very light but still scored well for holding many knots and slings.
Rope Pull Smoothness
The best carabiner for pulling the rope over was the Petzl Attache. It has a wide diameter and is almost perfectly round, making the rope pass over with minimal friction. It is no surprise that most guides use this carabiner when belaying a second in auto-block mode from the anchor. The Petzl Attache 3D scored nearly as well and is much lighter. Many other carabiners scored high and would make great belay carabiners. The super light mini carabiners scored the world.
The Black Diamond Rocklock and Omega Pacific Jake scored the best for gate clearance but there were many other carabiners close behind. The carabiners with the worst gate clearance were the small lightweight carabiners.
How to Choose the Best Locking Carabiner for You
Locking carabiners have evolved a lot in the last decade. They are lighter and are designed for more specialized tasks. There are few one-size-fits-all carabiners. Instead, certain carabiners are best for belaying, rappelling, and use in anchors and lightweight biners. Below, we look at key factors when choosing the best locking carabiner. – Chris McNamara
If you just are buying a carabiner for belaying at the gym or the crag, weight does not matter much. Every ounce is crucial if you are climbing multi-pitch routes or doing alpine routes. The difference between having six light locking carabiners on your harness or six standard locking carabiners is big. More importantly, light biners are much less bulky so they swing around less on your harness and don’t get stuck as much in chimneys.
The good news is there are more lightweight carabiners than ever. The challenge is finding a carabiner that can do everything you need at the right price. Most light biners work fine for general use, but do not excel at belaying, rappelling or use as a master point in an anchor due to their small size.
You lose some functionality with most light carabiners so make sure the weight saving is worth it. We discovered that the manufacturer’s quoted weight and the weight from our scale can differ by as much as five percent. This doesn’t mean you should trust our weight more than the manufacturers. But it does mean you should not get hung up on a few grams of difference when buying a light carabiner.
Gate Type: Screw-gate or Twist-lock?
Two main gate types are twist-lock (or quick-lock) and screw-gate. A twist-lock carabiner is the fastest to lock and unlock because you can take it off and on with just one hand motion. For this reason, they are ideal for gym climbing or cragging if you want to save time.
The screw-gate carabiners take more turns to close and you must remember to close them (twist-lock carabiners have a spring and close on their own). However, a screw-gate carabiner can feel more secure in an anchor because it is less likely that the gate will open accidentally if it is moved into an awkward position. This problem is addressed in some carabiners that use a ball-lock mechanism.
Screw-gate carabiners are usually 25 percent less expensive and lighter in weight. In general, twist-lock carabiners are best for belaying and rappelling and screw-gate carabiners are better for everything else.
When buying a screw-gate carabiner, consider how many twists it takes to open and close the gate. We generally prefer biners that take fewer twists because you save time. However, some people may feel safer if a carabiner takes more twists to open and close. Also, some gates will be more fluid when carabiners are brand new. Some biners can be opened and closed with one precise flick of the fingers, which is convenient.
Because you have to remember to close a screw-gate carabiner, it’s nice to have safety features as Petzl uses. They have a red stripe that disappears when the gate is closed. This helps remind you to lock the gate and also helps prevent over-tightening. Other manufacturers deal with the over-tightening issue by putting metal on the gate to stop the screw-gate mechanism before it hits the other side of the biner.
We prefer key-lock gates because they get hung up less on slings and bolt hangers. Most carabiners now come with key-lock options and generally don’t cost more so there is no reason not to go the key-lock route.
In addition, some key-lock carabiners are a little smoother to get on and off due to the angle of their key-lock; the smoother the angle the smoother the carabiner comes on and off. However, that is a pretty subtle distinction between key-lock carabiners. The main thing is to go key-lock when possible.
Number of Knots Held
If you use a carabiner in an anchor, especially as the master point, it’s nice if the biner holds lots of ropes and slings. Generally, the larger the carabiner, the better it is at holding lots of cord. That said, the shape also plays a role.
If a carabiner has a pear-shaped area below the gate, then more ropes and slings will fit in. A D shape or oval shape generally holds a little less. Lightweight carabiners hold very few ropes and slings because of their compact size limits their versatility.
Rope Pull Smoothness
How smoothly a rope pulls through a carabiner is essential if you belay a second climber off the anchor using an auto-block belay device like the Petzl Reverso 3. The wider and rounder the stock of aluminum, the smoother the rope will flow over it.
In addition, carabiners with more oval or pear shapes generally keep the rope from contacting the spine and therefore have less drag. The other instance where rope pull smoothness is nice is with top rope anchors, where it is nice to have a smooth pull. Other than those situations, smoothness is less important than other factors like gate performance, shape, and weight.
We found gate clearance less important than how many ropes a biner will hold. In general, you are only clipping one rope or sling at a time, and all gates work about the same. Only in very specialized applications, like using a locking carabiner with a big pulley, is gate clearance as big an issue.