The UIAA equipment standard provides a baseline for equipment performance in a test lab under controlled conditions on new equipment. Although these test conditions are relevant to the conditions encountered climbing, conditions encountered at the crags and the condition of the equipment are equally important. This recommendation from the UIAA member federation The British Mountaineering Council (BMC) provides vital equipment information that is NOT explicitly addressed in the standard, particularly failure modes of the equipment and recommendations for the use, inspection, maintenance, and retirement of equipment.
12mm Boa HMS Locksafe
The 12mm Boa HMS has a wide gate opening for easy clipping of thick ropes and slings, and large internal volume for controlled handling in all conditions. It's curved top bar allows multiple attachments which can centralise under load for stable loading.
HMS carabiners have extended top bars to accommodate multiple attachments like slings and knots. Their top bars are curved, allowing attachments to self centre and encouraging optimal loading. HMS carabiners tend to be large, for better compatibility with thick ropes and while wearing gloves.
The gate opening is the distance between the nose of a carabiner and the gate when it is fully opened. Larger gate openings make a carabiner easier to use while wearing gloves, and with thick ropes and slings. Internal volume refers to the area inside a carabiner, and large internal volumes mean easier attachment and removal of multiple devices, knots and slings.
These carabiners use thick 12mm bar to achieve very high strength ratings. They are suitable for heavy duty rigging operations where strength is paramount.
Steel carabiners are very strong and hard wearing, making them suitable for scenarios with high loads and heavy use. Cold forging means carabiners retain full section bars for consistent rope handling, while heat treatment results in high tensile strength.
In grams, the weight, as stated by the manufacturer/brand.
Rule of thumb
Almost every carabiner you use will be non-locking offset D’s, with the exception of a Pear/HMS locker as your belay ‘biner.
Offset D (aka Modified D)
60% of the market
A modification of the standard D shape, the top of an offset D is much wider, allowing for a larger (and superior) gate opening. When loaded, most of the weight is transferred to the spine of the carabiner making them stronger than most other shapes. Used for top and bottom quickdraws, as racking carabiners, and lightweight lockers.
Pear / HMS
22% of the market
The Pear/HMS carabiner is used primarily for belaying and/or setting a powerpoint in an anchor. The wide top means they can hold a lot of gear. They are almost always locking and are generally heavier (than D/offset D's) because they need more material to gain back strength lost due to their shape.
8% of the market
The first carabiner shape to be mass produced. When loaded, the pressure is shared equally on both sides of the ‘biner. Since the weaker gate shares the load with the spine, oval biners aren’t as strong as shapes that direct the load to the spine. The bonus is, your gear rests squarely in the middle, so it's great for holding nuts, pulleys, and prusiks.
D (aka symmetric D)
7% of the market
D’s have a symmetrical shape that sets the rope closer to the spine, putting the load on the spine (versus sharing the load with the weaker gate side, like the oval). Since the strongest part of the carabiner carries the weight, D’s are the strongest shape. Downside: Smaller gate openings than the offset D.
Quicklink (aka Oval link, Mallon)
1% of the market
Although most climbers wouldn’t refer to this shape as a “carabiner” they are certified by the same EN standard as all the other carabiners. These semi-permanent links ensure the gate will not accidentally open. They're used when setting up a semi-permanent rappel station (not used while climbing up).
Semi-Circle / 3D
less than 1% of the market
Semi-circle: Mostly used by Search and Rescue as this is a great way to secure a chest harness.
|Pear / HMS|
main non-locking carabiners uses:
main locking carabiners uses:
screw gate vs auto-locking gate
Screw gates are generally lighter and cheaper.
Auto-locking gates are usually considered safer as they automatically snap shut, not counting on one's memory to close and are harder to accidentally unlock. The debate comes on opening speed as some are much faster while others can be a struggle.
|Straight or Bent
Straight or Bent
It's easier to see the difference between straight and bent gates on solid gate carabiners:
The standard. Always used as the bolt-end of the quickdraw, and still sometimes used on the rope-side too. Also used for racking gear such as cam and nuts.
Created to make it easier to put the rope into a quickdraw with their larger gate opening. Primarily used on the rope-end (bottom) of quickdraws.
Many manufacturers are now making the bolt-end carabiner come standard in silver (to match the bolt color), and are coloring the rope-end with other anodizations.
Do not mix (interchange) bolt-end carabiners and rope-end carabiners. This can be very dangerous as small abrasions made by the bolt can easily wear your rope. DMM put out a great video/write-up on this issue.
Full size carabiners are easier to hold but generally they're also heavier.
This is a totally debatable field as there is no official size, weight, or gate opening necessary to be full size. There are no certifications and this isn't a standard the manufacturer's normally describe specifically.
We did our best to compare (descriptions, in-person use, etc), as a way to help give more information about this carabiner. Like always, if you see something that seems totally off, send us a note.
A keylock nose means the nose is smooth. Keylock carabiners are also known as: snag-free, notch-less, and hook-less.
The lack of a hooked nose makes for less snagging on gear and bolts – a dramatic improvement.
Given that they’re more complicated to manufacture, keylock designs often come at a higher price, especially in wiregates.
There are more design features necessary to guarantee a snag-free experience, like the curvature of the nose. Some keylock carabiners will still catch on the nose because of the lack of a smooth nose arc (smoother the arc, smoother the clip).
|Solid or Wire
Solid or Wire
Generally on beefier carabiners, so they're usually heavier and more durable. They can also feel more substantial in your hands while clipping. Often favored by sport climbers.
Featured on the lightest carabiners, so they're favored by trad and alpine climbers.
If you want keylock nose carabiners, then solid gates will be much cheaper compared to wire gates.
When wiregates first came out they were not trusted (too new, looked too simple). Now, it's proven that wiregates have less gate flutter and gate shutter than solid gates.
Gate Opening (mm)
Gate opening refers to the distance between a carabiner’s nose and the fully open gate.
top of your quickdraw: 17 mm – 22 mm
Adding bias towards a larger gate opening is a great option once you’ve narrowed your choice to a few similar carabiners and need help determining which one is the best.
|Number of Colors
Number of Colors
The number of different colors that you can find this carabiner in. This color-coding practice was started with just 2 colors, usually silver (that goes on the bolt side of a quickdraw) and another color for the rope side. Now, carabiners come in 5+ colors sets known as "rack packs" so your carabiners can match your cams.
Climbers can also match their carabiner color to their harness or other gear just for fun.
A visual warning is only seen on locking carabiners. It adds another tell to show if the carabiner is locked or not. If the carabiner is not locked, you'll see a warning such as the color red, a danger sign, or an unlocked image.
Only a small list of manufacturers add this safety feature, although you can easily add one yourself with a permanent marker.
In kilonewtons, the strength, as stated by the manufacturer/brand.
Major Axis Closed Gate Strength
This is the strongest orientation and the way carabiners are designed to be loaded.
Major Axis Open Gate Strength
This strength is measured because while climbing, carabiners lying against the rock can be opened slightly as they move across an uneven surface. A carabiner can also open slightly during a fall as the ‘biner starts to vibrate, dispersing the energy (also called "gate flutter"). A weak gate closure (due to a poor/failing spring or an over-stressed wire) could also leave the gate ajar.
Minor Axis Gate Strength
Carabiners are not intended to be loaded along the minor axis (cross-loaded), but it is possible for a carabiner to unintentionally rotate during use, especially while belaying. Of all accidental misuses of a carabiner, cross-loading is the most frequent suspect, which is why there is a rating for it.
Generally wire gates are stronger than solid gates in the minor axis. During the test, the wire gate bends, absorbing some of the force, as compared to a less pliable solid gate.
|40 kN 12 kN 10 kN|
This is a great belay device locking carabiner or all-around locker. We found it was one of the easier ones to operate with gloves, which makes it ideal for winter use. For belaying we liked the twist-lock gate version the best. The screw-lock gate is also effective, but we feel it is better suited for an anchor or backup biner.
How to use DMM Locking Carabiners, Maintenance and Servicing, warnings and lifespan with instructional pictures.
A pictoral representation of UIAA-121 and EN-12275 standards for connectors (the UIAA's fancy word for carabiners).