Here's everything you need to know about carabiners for climbing and rope activity


Safety approved carabiners - What does that mean? 

There are a number of different carabiners and it can be a bit difficult to set them apart. Various types include screw carabiners, HSE carabiners, D-carabiners, twist-lock carabiners and wire carabiners, all of which are used as part of the personal climbing equipment. A carabiner can be designed solely to carry equipment or it can be designed to hold your body weight. The strength of the carabiners depends on each individual product. Carabiners for climbing should at least always be CE marked or UIAA approved. It is first and foremost about safety, and therefore ALL our carabiners are CE marked or UIAA approved. Please note that we have put a volume discount on some of our best-selling carabiners.


Types of carabiners and wich to choose


The classic carabiner shape and also the most popular due to its multifunctionality. Oval carabiners are good, among other things, because their symmetrical shape allows them to be rappelled with and minimizes load displacement, and in addition, the shape has room for a lot of equipment. On the other hand, the strength is hardly as high as other carabiners and the opening is also typically a bit smaller.


Although the oval shape is the most popular, the D-shape is preferred by climbers as it moves the weight away from the side where the opening sits. D-shaped carabiners are light, stable, durable, and the strongest type, but often also smaller than other shapes, cost more than the oval shape and the opening is only slightly larger.

Asymmetric D-shape

The asymmetrical D-shape, also known as modified D-shape, works just like the D-shape, but the bottom is a bit smaller and therefore weighs less and often also has a larger opening. Therefore, the asymmetrical D-shape is also one of the most widely used carabiners by climbers. The larger opening makes it easier to clip ropes and equipment into the carabiner, but the asymmetrical design also means that there is less space and is a bit more expensive than the D-shape. The asymmetric D-shape is strong but not quite as strong as the normal D-shape.

Bulb shape (HMS)

Like the asymmetrical D-shape, the pear shape has a large opening so you can easily clip ropes and equipment into the carabiner. They are designed specifically for securing and rappelling, but can also be used to set anchors for top rope or multi-pitch climbing. Pear-shaped carabiners are often the most expensive shape and are not quite as strong as D- and asymmetrically D-shaped carabiners. Pear-shaped carabiners are also known as HMS carabiners, which are also sometimes marked on the carabiner. This means that the carabiner has a wide symmetrical top that works well for use with an HMS knot that you can use to secure with. 


The different gate types in carabiners

Straight gate

Straight gate is the strongest gate type. It is durable and easy to use, therefore they are also very common to find on carabiners. These carabiners are often used for Quickdraws or for holding equipment. As the gate is completely straight, it is also this type of gate that is used with all carabiners with a locking mechanism. However, straight gate carabiners are not as light as wire gate carabiners.

Bent gate

Bent gate is just like straight gate, very durable and easy to use and heavier than wire gate. The curved gate makes it easier to clip the rope into the carabiner with one hand, and therefore bent gate carabiners are also used for Quickdraws as the carabiner you clip the rope into.

Wire gate

Wire gate is a wire made of stainless steel, which makes the carabiner a lot lighter and gives a larger opening as it requires less space. In bent and straight gate carabiners, there is a spring that makes the gate close automatically, in a wire gate the automatic closing is part of the design. The fewer parts in a wire gate, make it even easier and minimize the risk of the gate freezing in cold and wet weather. Although wire gates look less durable than bent and straight gate, they are often just as strong.


Locking mechanisms in carabiners explained 

Carabiners with a straight gate may have a locking mechanism that makes the carabiner safer to use, as the risk of the gate opening at an inappropriate time is removed. Locking mechanisms can be both manual and automatic, both with their own advantages and disadvantages, for example, you still need to remember to check if an automatic lock is closed properly. Carabiners with a locking mechanism are used to secure with and when safety is critical.


A screw-lock is a manual lock that works by screwing a cover over the top of the gate and the carabiner opening, thereby preventing the gate from opening. As this is a manual lock, it is important to check if it is locked every time you use it.


A twist-lock is automatic that requires two movements each time it needs to be opened. First, the sheath over the gate must be rotated, often 90 °, and then the gate will be opened. When the gate is released again, the gate closes and the cover rotates to the locked position automatically. Twist-lock is simple and quick to use and means that you do not have to manually lock the carabiner every time. On the other hand, do still remember to check the carabiner every time. 


Tri-lock is a variant of twist-lock that requires a third movement before the other two, of which "tri "comes from. The third movement that must take place before the other two, is that the cover that sits over the gate must be pushed up, after which it can be rotated and the gate can be opened. Like the Twist-lock, the tri-lock also locks automatically when the gate is released. The extra movement makes the tri-lock safer than the other two but is also a bit more inconvenient.


A pinch lock is a relatively rare lock where you have to press a button on each side of the gate before the gate can be opened. A variant of pinch-lock is botton-lock, where there is a button on the inside of the gate that must be pressed in before the gate can be opened. Both lock types are automatic.


The impact of size, material, weight, and strength in carabiners


The size of a carabiner greatly influences its capabilities and functionality regardless of the carabiner type. Larger carabiners are often easier to handle, clip ropes into, and equipment into as the opening is also larger and there is room for more. At the same time, they can also be stronger. Larger carabiners will often be used for securing and rappelling. Smaller carabiners weigh and take up less space in the harness but are in turn difficult to clip into.

Opening Size

The size of the carabiner opening is something you may need to be aware of. It is measured in millimeters and is determined by the carabiner type and size. If the opening is too small, one's fingers can get caught between the gate and the carabiner, and if the opening is too large, it can be difficult to handle.

Carbine material and weight

Carabiners are made of two different materials, aluminum, and stainless steel. Aluminum is a lot lighter than steel, which in turn is stronger and more durable. This means that when you have to lug around several carabiners, it is an advantage that they are made of aluminum due to the weight advantage, where steel carabiners are perfect where it has to be fixed and hold for a long time. It does not matter so much that a carabiner is a little bigger and weighs a little more when it is to be used for securing or rappelling, but when you need to use a lot of carabiners, for example with Quickdraws, suddenly it makes a difference to have a lot of extra weight.

Maintenance and disposal of carabiners 

As you use your carabiner dust and dirt can slowly build up i the joint of the carabiner gate. When the joint starts to gunk up it can becomes harder to open the carabiner it also increase the risk of the carabiner not closing correctly. In order to lubricate the carabiner to allow it to open and close smoothly again it is crucial that you do not use any kind of oil or liquid-based lubricant as that would only result in more dust and dirt sticking to the carabiner. Insted you should get your hands on some graphite powder. Graphite powder is microscopic balls of carbon with incredibly low friction which will allow the carabiner gate to move freely.

When to discard and how to dispose

When should you discard a carabiner? Here are two rules of thumb which will make it easy to remember:

  1. After a fall with a fall factor above 1, all equipent should be discarded.
  2. After a drop onto a hard surface from above 2 meters or if visibly damaged.

If you end up in a situation where you need to discard a carabiner you can simply throw it out with your other metal trash. If the carabiner is visibly severly damaged, say the gate is completly missing, you do not have to take any extra messures. If however the carabiner looks just fine it is recomended that you attatch a note to the carabiner saying it has been discarded, you can do this with a piece of tape. This is also recomended for other hard equipment as it can not be cut to be made useless as is standard procedure with soft equipment. The reason you should cut or attach a note is to prevent others from finding and using the equipment thinking its good to go which could end poorly.

Have any questions about carabiners? Don't hesitate to reach out! We're always happy to help. 

- Julie


About the author 
Julie Gjørtz

Digital Marketing Manager & Boulder
As Gubbies Digital Marketing Manager, it's Julie's job to keep up with the freshest information from the climbing world and communicate them to you. Have any questions about anything she writes? Don't hesitate to reach out!  She can't wait to share her climbing-geekiness with you!