Load rating.
This refers to the maximum tensile force that a climbing buckle can withstand, usually expressed in kilonewtons (kN). Climbing buckles of different types and uses have different load ratings. Generally, climbing buckles for rock climbing should reach at least 20 kN, while diving buckles should reach at least 5 kN.
Type of lock.
This refers to the opening and closing methods of mountain climbing buckles. There are three common types: straight doors, spiral doors, and self-locking doors. Straight doors are the simplest type of door that can be opened or closed by pressing the spring, but they are also the most likely to be accidentally opened or jammed. The screw door is a screw locking device added to the straight door to prevent accidental opening, but requires manual rotation to lock or unlock. Self locking doors are the safest type, which can automatically lock and unlock, and can be opened or closed by pressing and holding a button.
Rust resistance.
This refers to the ability of climbing buckles to resist corrosive factors such as moisture, sweat, and dust. Mountaineering buckles made of different materials and processes have different rust prevention properties. Generally, aluminum alloy and stainless steel are more durable.
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