Guide · Carabiners and connectors
Carabiner gates and loading direction: what connector makers say
Petzl's connector principles (major axis, gate closed, nothing pressing on the gate), what 12 kN on a gym carabiner means, and breaking strength vs working load.
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Picks that fit
- Fusion Climb Tacoma Steel 50KN Auto Lock Carabiner (Gold)Check price on Amazon
- Black Diamond HotForge Screwgate Carabiner (Gray)Check price on Amazon
Short answer
Connector makers agree on the basics: load a carabiner along its long axis, with the gate closed (and locked, if it locks), and keep anything from pressing on the gate. These principles come from climbing and work-at-height makers, not gym makers. A kN figure on a carabiner is a breaking strength, never a weight you can put on your cable.
Picks that fitAll picks and how to choose
- Fusion Climb Tacoma Steel 50KN Auto Lock Carabiner (Gold)Check price on Amazon
- Black Diamond HotForge Screwgate Carabiner (Gray)Check price on Amazon
Where these principles come from
The clearest guidance on carabiner loading comes from Petzl, which makes connectors for climbing and work at height. Its rules are written for that equipment. We quote them as general principles, not as a gym maker's rule, and no gym maker in our sources sets its own.
Petzl's principles
- Major axis, gate closed, sleeve locked. Petzl's carabiner basics page says that for vertical loads only the major-axis, gate-closed strength is suitable, and that carabiners should be loaded on the major axis with the gate closed and the sleeve locked.[1]
- An open gate is much weaker. Petzl's instructions for a locking carabiner say it is strongest when closed and loaded on its major axis, and its strength is greatly reduced if the gate is open.[2]
- Nothing presses on the gate. Petzl's connector instructions say the connector must always be used with the gate closed and locked, and any external pressure on the gate is dangerous.[2]
- Wide parts can weaken it. Petzl notes that wide webbing or large bars connected to the carabiner can reduce its strength.[3] A thick eyelet on a cable attachment is worth checking against that.
- Check before each use. Petzl tells users to check that the frame, gate and locking sleeve are free of cracks, deformation and corrosion, and that the gate closes and locks by itself when released.[2]
On locking, Petzl describes a trade-off: security against ease of use, with a secure lock reducing the chance of accidental opening.[1]
What gym carabiner numbers mean
Two gym listings show why a strength figure needs its label:
- MakeIt states a 12 kN rated breaking strength for its cable-machine carabiner, and says this must not be confused with a recommended working load.[4]
- Power Systems' carabiner listing states a "550 lb load" without saying whether that is a working load or a breaking strength.[5]
Do not convert 12 kN into pounds and treat the result as a gym limit. A breaking strength is the force at which the part fails in a test, not what you should load it with.
Breaking strength vs working load
Industry separates the two with a design factor. Certex defines it as the ratio of a rope's breaking strength to its maximum working load.[6] Those factors are set for industrial rope and rigging. They are not gym rules, and you should not apply them to a gym carabiner to work out a load.
A proof load is different again. Lexco describes it as a controlled, measured force applied to an assembly for a set time, after which the assembly is inspected for defects.[7] It is a factory test. Never proof-load your own gear.
If a carabiner's maker does not state a working load or rating for your use, the safe working figure is unknown. Ask the maker.
Locking carabiners with stated gates
These are climbing and rigging carabiners, not gym products. Their kN figures are strengths for their makers' own uses, not gym ratings.
Picks that fit3 products
Fusion Climb Tacoma (Gold, single): steel auto-lock, so the gate locks itself when it closes; 0.95 in gate opening; 50 kN major axis is a breaking strength.
More on choosing
Fusion Climb Tahoe XL (Black, single): steel manual screw-lock with a 1.25 in gate opening. Black Diamond HotForge (Gray, single): aluminum screwgate with a 19 mm gate opening, for smaller eyelets. On Amazon, check that 'Ships from / Sold by' is Amazon.com or the brand.
Steel auto-locking carabiner with a wide gate
Fusion Climb Tahoe XL Steel Screw Lock Key Nose Carabiner (Black)
Black Diamond HotForge Screwgate Carabiner (Gray)
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Questions
Should I use a locking carabiner on a cable machine?
No gym maker in our sources requires one. Petzl describes the lock as a trade-off between security and ease of use, saying a secure lock reduces the chance of accidental opening; compare the gates documented for the carabiners you are considering.[1]
What does 12 kN mean for my cable machine?
It is a breaking strength, not a weight you can lift. MakeIt states 12 kN for its gym carabiner and says it must not be confused with a recommended working load.[4]
Is it bad if the carabiner loads on its gate?
Petzl's connector instructions say any external pressure on the gate is dangerous and that strength is greatly reduced if the gate is open. Reposition so the load sits on the spine end with the gate closed.[2]
Can I work out a safe gym load from a carabiner's breaking strength?
No. Design factors like those Certex describes are industrial rules for rope and rigging, not gym gear. Use only a working load or rating the carabiner's maker states for your use.[6]