The Difference Between Karabiner Locking Mechanisms

Our range of karabiners/connectors/mallions are available with different locking mechanisms. These locking mechanisms have one major thing in common and that’s to prevent the accidental opening or unlocking of the karabiner.

SCREWGATE (SCREW-LOCK)

Mechanism:

A screwgate system involves a karabiner with a gate that can be manually threaded to lock it in place, covering the nose and preventing the gate from opening. The user must rotate the sleeve (usually in a clockwise direction) to secure the gate.

Pros:

• Simple and easy to use.
• Reliable for general use when completing tasks at height and other activities.
• Usually most affordable.

Cons:

• Requires manual locking, which means there’s a risk of forgetting to screw it tight.
• Slightly slower to operate, especially in emergency situations.

Our offering:

Code	Description	Gate opening
RGK1	Steel screwgate karabiner	17mm
RGK1/A	Aluminium screwgate karabiner	21mm
RGK7	HMS/belay screwgate karabiner	26mm

SEMI-PERMANENT MALLIONS

Mechanism:

Similar to the screwgate system, the semi-permanent mallion has a gate that can be manually threaded to lock in to place, a spanner is commonly used to tighten the gate further. The user must rotate the sleeve (usually in a clockwise direction) to secure the gate.

Undo the gate

Pros:

• Simple and easy to use.
• Can’t be opened without a spanner, safe for inexpereinced climbers in recreational settings.
• Reliable for general use when completing tasks at height and other activities.

Cons:

• Requires manual locking with a spanner, which means there’s a risk of forgetting to screw it tight.
• Slower to operate due to best practice of tightening with spanner.

Our offering:

Code	Description	Gate opening
RGK12	Steel screwgate delta link mallion	10mm
RGK20	Steel screwgate half circle mallion	10mm

SINGLE ACTION (NON-LOCKING)

Mechanism:

Our single action karabiners are spring loaded. They require the user to simply push the gate to open and then on release will automatically close.

Press the gate

Pros:

• Highly efficient in situations where speed matters.
• Extremely quick mechanism for opening or closing, designed for recreational climbing, for items such as a quickdraw.

Cons:

• Requires a manual push, risk of accidentally opening the gate.
• The solid gate versions can suffer from gate flutter, rapidly opening and closing when a rope runs through at speed.

Our offering:

Code	Description	Gate opening
RGK23	Bent gate aluminium karabiner	23cm
RGK24	Wire gate aluminium karabiner	22cm

DOUBLE ACTION (SNAP HOOK)

Mechanism:

This system requires the users to perform two actions to open it, which is usually a squeezing action of the front and back of the connector. Commonly in the form of a hook.

Pros:

• Once released the hook locks automatically.
• Fast and convenient to use with little effort.

Cons:

• More expensive and sometimes heavier.
• If not maintained well, the locking mechanism may be hindered.

Our offering:

Code	Description	Gate opening
RGK10	Steel snap hook	19mm
RGK11	Aluminium scaffold hook	60mm
RGK11/SL	Lightweight aluminium scaffold hook	55mm
RGK11/LSH	Large aluminium scaffold hook	110mm
RGK45	Steel swivel snap hook	21mm
RGK88	ANSI aluminium scaffold hook	62mm

DOUBLE ACTION (TWIST-LOCK)

Mechanism:

The twist-lock system requires the user to twist the sleeve to unlock it, often with a quick twist action. This is generally an automatic system, once the gate is released it locks thanks to an internal spring.

Pros:

• Faster than a screwgate, as it requires less manual effort.
• Provides a secure and quick mechanism for locking/unlocking.
• Automatically locks once released.

Cons:

• Still requires a manual twist, small risk of mis-locking if not done correctly.
• Likely more expensive and heavier than screwgate systems.

Our offering:

Code	Description	Gate opening
RGK2	Steel twist-lock karabiner	17mm
RGK3	Steel twist-lock karabiner	24mm
RGK5	Steel twist-lock scaffold karabiner	56mm
RGK6	Aluminium twist-lock scaffold karabiner	54mm

TRIPLE ACTION (TRIPLE-LOCK)

Mechanism:

Offering an additional level of security through a triple-lock action. The user must perform three actions to unlock the karabiner:

Pros:

• Provides the highest level of security, reducing the chance of accidental opening.
• Ideal for situations where safety is critical, such as when connecting to fixed anchors in climbing.

Cons:

• More time-consuming and slightly complex to use compared to the other systems.
• Can be inconvenient in situations where fast access is needed.

Our offering:

Code	Description	Gate opening
RGK1/AT	Aluminium triple action karabiner	21mm
RGK15	Steel triple action karabiner	12mm
RGK18	ANSI steel triple action karabiner	18mm
RGK19	Steel triple action karabiner	23mm
RGK22	Pear shaped aluminium triple action karabiner	22mm
RGK44	Aluminium triple action swivel karabiner	22mm

SUMMARY OF KEY DIFFERENCES

Locking system	Security	Speed of use	Ease of use	Complexity
Screwgate	Moderate	Slow	Easy	Low
Semi-permanent	High	Very slow	Moderate	Medium
Single action	Low	Fast	Very easy	Low
Snap hook	Moderate	Fast	Easy	Medium
Twist-lock	Moderate	Fast	Easy	Medium
Triple-lock	High	Slow	Moderate	High

Each locking system has its strengths and trade-offs. The choice of system often depends on the activity, the desired level of security, and how quickly you need to open and close the karabiner/connector.

For a lot of general tasks at height (scaffolders, construction, telecoms), screwgates, double action snap hooks and twist-locks are common, but for high-security needs (e.g., rope access tasks), triple-lock are more appropriate or semi-permanent especially for recreational settings with inexperienced climbers and children.