Carabiners are essential to any climber’s gear, attaching to harnesses, anchors, or ropes themselves, and preventing countless falls every day of a climber’s life. They are extremely strong, can hold a great deal of weight, and keep climbers moving up or down a rock wall or cliff-face safely.
Of course, like everything in the climbing world, the carabiners come in numerous sizes and shapes, and it may be difficult to figure out which is the best carabiner for your purpose. This is why it is necessary to understand all the features of these handy items, from size and weight to locking mechanisms.
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DMM Big BOA Key-lock Locking Carabiner
Weight: 83 g
Dimensions: 24 mm gate opening
Specific Features: Large gate opening, strong I-Beam construction, 25kN with gate closed, 8kN with gate open, 10kN on minor axis
Best Use: Climbing, belaying, rappelling
Description: This large clean nose HMS locking DMM Big BOA Key-lock Locking Carabiner is perfect for any rigging situation, and is capable of accommodating multiple knots at once.
The large gate opening makes it easy to use with numerous rope sizes with no snagging, and it easy to handle, whether bare-handed or in thick gloves, so it is great for both summer and winter climbers. Its strong anodized I-beam construction makes it sturdy and durable, while still reducing the weight when compared to other models.
The locking feature ensures it won’t open without twisting the screw lock, for added safety, and it is available with a Screwgate, a Quicklock, and a Locksafe locking system, to meet the needs of any user. Though the body is always silver, you can choose one with a gold, red or green gate.
They are decently priced, especially since their strong construction and amazing safety features mean they will last for years.
Related: DMM also has a BOA HMS 30kN that is similar to this model, including the large gate opening, the ability to hold several knots, and the strong I-Beam construction.
It is heavier, but can also handle more weight, up to 30kN. For heavier loads, this may be a better option, but the smaller model may be better for those who prefer lighter loads.
Metolius Element Key-lock Carabiner
Weight: 73 g
Dimensions: 3.8 x 2.4 inches, 19 mm gate opening
Specific Features: 24kN Major Axis strength, 8kN Minor Axis strength, 8kN with gate open
Best Use: Multi-pitch climbs, belaying, rappelling, homemade ziplines
Description: The hot-forged metal of this Metolius Element Key-lock Carabiner is extremely durable, and the pear-shaped design makes it the perfect tool or belaying or rappelling.
The key-lock feature requires a few flicks to open, and though some users found this to be a bit of a hassle, many appreciate the increased safety of this design, knowing it will never come open unless they intend it to.
The large diameter gives the rope plenty of room for a variety of knots, and the smooth texture means your rope will always pass easily through it. This carabiner has been tested up to half of its rated strength, and passed with flying colors, giving its users that extra sense of security when using it.
The Metolius Element carabiner is small, compact, and comes with a low price tag that makes it well worth the purchase, no matter how often you use it. This workhorse belay and rappel carabiner comes in either black or green.
Related: Metolius has a few other similar carabiners, the Bravo Locker and the Steel Locker. Both come with screw lock gates, but are heavier than the Element. The Bravo is smaller and thinner, but still high strength and easy to use.
The Steel Locker is much larger, and better suited to heavy-duty environments. For regular climbs, or normal use, the Element is probably the best choice.
Petzl AM’D Screw-Lock Carabiner
Weight: 70 g
Dimensions: 4.41 x 2.6 x 0.66 inches, 25mm gate opening
Specific Features: Aluminum construction, 27 kN Major Axis strength, 8 kN Minor Axis strength, 8 kN with gate open
Best Use: Belaying, rappelling, climbing, carrying gear
Description: With the asymmetrical D-shaped design, this handy Petzl AM’D Screw-Lock Carabiner is excellent for belaying, with the ability to use either end with ease, and it is strong enough to hold your equipment.
It is versatile enough to connect to a variety of items, such as descenders or positioning lanyards, and due to its smooth aluminum surface, ropes will not snag or get hung up when you pull them through.
The shape and design also makes it easy to manipulate, whether bare-handed or wearing gloves. The screw-lock system needs multiple turns to open it, so there will be no risk of it slipping open and becoming dangerous to use.
There have been some who have complained that it locks too tightly, and may not be easy to open quickly, but others have found this to be a comfort. The AM’D comes in a stylish black that won’t draw too much attention, and along with the screw-lock design, it can also be purchased with a ball-lock or a twist-lock, to meet the needs of all its users.
Related: There are two Petzl carabiners that offer the same uses as the AM’D. These are the William and the Spirit. Both have screw-lock functions, though the William also comes with a ball-lock option for those who prefer it.
The William is also heavier and has a higher Major-axis strength, better suited for heavy duty climbing, while the Spirit is lighter and can hold less weight. The AM’D is middle of the road, and a great option for all climbers.
Mad Rock Ultra Tech HMS Screw Carabiner
Weight: 67 g
Dimensions: 96 mm x 65 mm, 22 mm of gate clearance
Specific Features: Aluminum body, forged I-Beam construction, 27 kN Major Axis strength, 9 kN Minor Axis strength, 9 kN with gate open
Best Use: Climbing, hiking, camping, hanging hammocks
Description: This hot-forged aluminum Mad Rock Ultra Tech HMS Screw Carabiner is extremely durable and tough, capable of carrying a great deal of weight, whether climbing a rock wall, holding you up in a hammock, or keeping your dogs on their tie-lines.
The Ultra Tech HMS is a great addition to any belay device, thanks to its smooth body and no snag gate. It is a bit larger than some other models, and some may find it a bit too much for their needs, but it is perfect for heavy-duty use and a multitude of functions.
Some people who have used this carabiner in wetter weather, and even with prolonged outdoor use, are pleased with the lack of rust environmental wear. The screw-lock holds tight, and won’t come open on its own, which is an excellent safety feature.
The Ultra Tech has a low price for its durable frame and ease of use, and comes in shiny silver with a red gate.
Related: There is also a regular Ultra Tech Screw carabiner, but it does not have the HMS design.
It is still a great carabiner, and is lighter in weight, but is not as useful for those who prefer the Munter Hitch, since this carabiner is not shaped for it to be used properly.
Petzl Attache Screw-Lock Carabiner
Weight: 80 g
Dimensions: 3 x 2.7 x 0.4 inches, 20 mm gate opening
Specific Features: Aluminum construction, 23 kN Major Axis strength, 7 kN Minor Axis strength, 6 kN with gate open
Best Use: Climbing, belaying, rappelling, hunting, military search and rescue
Description: This compact and lightweight Petzl Attache Screw-Lock Carabiner is easy to use, with a screw-lock function that stays closed at all times when in use, keeping your eyes up on the rock in front of you, on other climbers, or down at the ground while you rappel back to the bottom.
It attaches easily to a harness, and works perfectly with a Munter Hitch, with the rope sliding easily through it when belaying.
The pear-shaped Attache has multiple uses, whether climbing for fun or as part of a search and rescue mission, carrying your gear, hoisting up a deer after hunting, and much more.
The aluminum body is strong enough to be used for months of regular climbing with no signs of wear, and the lock has a red indicator line, so you always know when it is open or closed. The rest of the body is black, and though it has a bit of a higher price tag than other carabiners, its durability and easy use makes it well worth the price.
Related: The closest carabiner to Petzl’s Attache is the William, which has the same pear-shape best used when belaying with a Munter Hitch, the same screw-lock system, and the same aluminum body.
The William is bigger and heavier, and better suited to heavy work, while the more compact Attache is more versatile for regular or daily use.
Black Diamond Mini Pearabiner
Weight: 69 g
Dimensions: 20 mm gate opening
Specific Features: 24 kN Major Axis strength, 7 kN Minor Axis strength, 8 kN with gate open
Best Use: Climbing, belaying, rappelling, biking
Description: This lightweight Black Diamond Mini Pearabiner is compact, easy to use, and works well with other climbing gear, including an ATC and a figure eight. It is versatile, and can be used with either one or two ropes for belaying.
The key-lock nose keep the ropes from snagging when sliding through, though some who have used this model have complained that the wider end is a bit flat, and dual ropes do not slide through as smoothly as with a rounder end.
The sleeve locks on the carabiner’s gate will never freeze up when loaded with equipment or other weight. This carabiner also comes with a pair of HDO Lite E-tip Gloves that have grippers on the palms and fingers to ensure you won’t slip when climbing, belaying, or unscrewing the Mini Pearabiner.
The gloves are black with white grippers, and the carabiner is silver, with a black gate and an orange screw-lock. Though by itself, the Mine Pearabiner would be a bit higher in price than some other models, with the included gloves, it’s a steal.
Related: Black Diamond has a similar screw-gate carabiner available, the VaporLock. It has a similar pear shape, has the same key-lock function and screw-gate sleeve, and only weights 52 g. It does not have the same high kN rating, and so is better used with only lighter weight gear.
Black Diamond Rocklock Screw-gate Carabiner
Weight: 85 g
Dimensions: 21 mm gate opening
Specific Features: 24 kN Major Axis strength, 7 kN Minor Axis strength, 7 kN with gate open
Best Use: Belaying, rappelling, climbing
Description: This heavy-duty Black Diamond Rocklock Screw-gate Carabiner is the largest made by Black Diamond, and is great for rough use on rugged terrains. It can be used easily with a Munter Hitch, and is excellent for both belaying and rappelling, especially since it can be operated with only one hand.
Even if you’re wearing gloves, there is still no hassle when trying to open the screw-lock. The key-lock nose keeps the ropes from snagging and slowing down your climb. The spine of this carabiner has a slight curve to it, which maximizes the gate opening and allows larger ropes to pass through it with ease.
The square hinge end keeps the belay loop secure and in place. The durable finish is strong and resists any scratches, even when used around sharp, grainy surfaces.
Some who have used this love the screw-lock gate, though have mentioned that it would be more comforting if there was an lock/unlock indicator that other models have included, to be sure you aren’t climbing with an open gate, but this is a small flaw, and doesn’t affect its use.
Related: Black Diamond has also made a Rocklock with a twist-lock sleeve, rather than the screw-lock this model uses, but all other features are the same.
Both are great, and which one you choose depends only on your locking preference.
Petzl Pro Attache Screw-Lock Carabiner
Weight: 56 g
Dimensions: 3.6 x 3.8 x 0.7 inches, 24 mm gate opening
Specific Features: Aluminum construction, 22 kN Major Axis strength, 7 kN Minor Axis strength, 6 kN with gate open
Best Use: Belaying, rappelling, military use
Description: This lightweight, pear-shaped Petzl Pro Attache Screw-Lock Carabiner is compact, yet strong enough for regular use with little wear on its surface. It is ideal for any belay station, and has an H-shaped cross section that gives it an upgraded strength to weight ratio.
The carabiners contact surfaces are wider than other models, giving the rope a larger area to slide through and reducing the friction that could damage the finish.
The screw-lock sleeve is easy to use and locks securely every time, with a red indicator line to show you when it is closed up tight or left a bit open. The key-lock system will not catch on your ropes, keeping their movement smooth and snag-free.
The shape of this carabiner has been adapted to easily tie or untie a clove hitch. When belaying, it is quite versatile, allowing use with a harness, or simply belaying with a Munter Hitch. Its bright orange color will help to keep it visible if ever dropped, so there is little chance of losing it.
Related: There is a Petzl Attache, which we have reviewed above, that is heavier and has a slightly higher strength rating, for those looking for a more heavy-duty carabiner.
Features to Look for in A Locking Carabiner
The best locking carabiner for you depends on what you will be using it for, from belaying to hauling gear.
They come in different sizes and weights, and have a variety of locking mechanisms, along with a few other details you should watch out for when choosing your carabiner.
Yes, size does matter with carabiners. Larger carabiners are easier to clip, and can hold more of your gear. They can also accommodate more knots than smaller carabiners, so if you’re unsure which size you need, always go a bit bigger, just in case.
The weight of a single carabiner may not seem like much, but consider the fact that you will need quite a few of them when climbing a big wall rack.
Even if you choose a lightweight 60 g carabiner, when you have to carry 30 of them with you while climbing, that adds up to almost 4 pounds of additional weight. Lighter is always better in this case.
Carabiners usually come in either steel or aluminum, and each has its benefits:
- Steel is stronger, more durable, and rather heavy. These carabiners are best used for high-use situations, including as gym anchors and quickdraws.
- Aluminum is much lighter, though still durable enough to last for years. They shouldn’t be used on fixed on routes.
All carabiners have strength ratings for the longitude and when cross-loaded (loading from gate to spine).
Though these numbers may seem important in regards to a carabiner’s strength, all carabiners are made strong and will not break under you or your equipment’s weight. Choose the higher number if you want, but don’t rely on it when there are other more important features to look for.
Carabiners can come in four different shapes, with varying strengths and uses.
- Ovals are the original shape, and are still manufactured by many companies. Those who make them claim they can rack more gear than any other type of carabiner. They usually cost less, but are not as strong or easy to use, and are heavier than other shapes.
- D-shaped carabiners are lighter and stronger than ovals.
- Asymmetrical D-shaped carabiners are upgraded from the regular D’s, and are the lightest and strongest design available. The gate opening is also larger, which makes them easier to clip or rack gear with.
- Pear-shaped models are usually the largest of all, and are best used with a belay or rappel device.
Locking or Non-locking?
Though all carabiners have closing gates, not all of them have locking features. This has nothing to do with their strength or durability, but can affect the climber’s safety.
- Non-Locking carabiners can be opened just by pushing the gate. Though these are safe during simple climbing, there is always the chance that they could be caught on something that pushes the gate open without your knowledge, releasing the carabiner and compromising your safety.
- Locking carabiners are designed to be manually opened and closed, using either a screw-gate or a twist-lock. These have to be turned until tightly locked, and won’t catch and pop open during your climb.
The difference between these two types is that the screw-gate must be used with two hands, with one on the carabiner and the other screwing the sleeve, while the twist-lock can be opened with one hand, first pressing down and then twisting it open.
This is one of the most important features to look for in a locking carabiner. Some models have only a notch in the nose that can hook the head of the gate by a tiny bar. These can be a hassle, though, because of the possibility of the nose sticking out the slightest bit, catching on the ropes or anything else it may brush on.
The key-lock closure solved this issue, because the gate on these types inserts into the carabiner’s nose as perfectly as a puzzle piece. This prevents any catching on a rack of nuts, or nose-hooking the hanger of a bolt.
Now that we’ve discussed the various features of a carabiner, it’s time to look at the top rated products in the market.
Carabiners, especially locking ones, are a necessary safety item that no climber should ever be without.
Their high strength and incredible features can keep you climbing without fear, and when you’re back on solid ground again, they are available to serve a multitude of purposes throughout your daily life.
Of course, if you think we have missed a quality carabiner in our list, please feel free to let us know in our comments section.
Daniel is a gear freak when it comes to hiking, climbing and camping. He went to REI Outdoor School to meet new people and learn best practices. Don’t even try to argue with him about the latest backpack or ice axe, he tried most of them. Daniel’s dream is to climb Mount Everest.