Which two units are used to express the carabiner weight rating in the material?

• A. kg and N
• B. lb and g
• C. KN and lbs
• D. N and J

Answer: (C)

The weight rating on a carabiner is a measure of force, not mass. That’s why it’s expressed in units of force. In the metric system, kilonewtons (kN) are used, and in the imperial system, pounds-force (often just written as pounds) are used. So the two units that commonly express the carabiner’s weight rating are kilonewtons and pounds because they both quantify the same idea—how much pulling force the carabiner can safely handle—across different measurement systems. Using mass units like kilograms or grams isn’t appropriate for a rating of load capacity, and energy units like joules aren’t relevant here.