## Common ground
All options are safety carabiners made from different metallic materials, each chosen for specific mechanical or environmental properties.
## Options at a glance
**7318.2X – Iron/Steel**
- **Defining trait:** Highest tensile strength and durability; prone to rust without coating.
- **Typical examples:** Industrial climbing, rescue operations.
- **Best fit when:** Maximum load-bearing strength is critical, and corrosion resistance is managed.
**7415.33 – Copper**
- **Defining trait:** Low strength but excellent conductivity and non-sparking; rare in safety gear.
- **Typical examples:** Explosive environments (e.g., mining).
- **Best fit when:** Non-sparking properties are essential, despite lower strength.
**7508.90 – Nickel**
- **Defining trait:** High corrosion resistance and heat tolerance; expensive.
- **Typical examples:** Marine or chemical industry use.
- **Best fit when:** Exposure to harsh environments (saltwater, acids).
**7616.10,7616.99 – Aluminium**
- **Defining trait:** Lightweight with good strength-to-weight ratio; prone to fatigue over time.
- **Typical examples:** Mountaineering, sport climbing.
- **Best fit when:** Weight is a priority and loads are moderate.
**7907.00 – Zinc**
- **Defining trait:** Very low strength and poor durability; not used in load-bearing safety gear.
- **Typical examples:** Decorative or non-critical fasteners.
- **Best fit when:** None for actual safety carabiners—likely a misclassification.
**8101.99 – Tungsten**
- **Defining trait:** Extremely dense and strong, but brittle and very expensive.
- **Typical examples:** Specialized high-stress applications (rare).
- **Best fit when:** Extreme strength needed in minimal space; not standard.
**8102.99 – Molybdenum**
- **Defining trait:** High-temperature resistance and strength, but brittle and costly.
- **Typical examples:** Aerospace or high-temp industrial use.
- **Best fit when:** Extreme heat exposure; not typical for general safety use.
**8104.90 – Magnesium**
- **Defining trait:** Lightest metal; flammable in powder form, weak under stress.
- **Typical examples:** Aerospace prototypes (not safety gear).
- **Best fit when:** Weight reduction is paramount and fire risk is controlled.
**8108.90 – Titanium**
- **Defining trait:** Excellent strength-to-weight ratio and corrosion resistance; expensive.
- **Typical examples:** High-end climbing, diving, military use.
- **Best fit when:** Need for light weight, high strength, and long-term durability.
## Key differences
| Material | Strength | Weight | Corrosion Resistance | Cost |
|----------------|----------|---------|------------------------|----------|
| Iron/Steel | Very High| Medium | Low (unless coated) | Low |
| Copper | Low | Medium | High | Medium |
| Nickel | High | Medium | Very High | High |
| Aluminium | Medium | Low | Medium | Medium |
| Zinc | Very Low | Low | Low | Low |
| Tungsten | Extreme | High | High | Very High|
| Molybdenum | High | Medium | High | Very High|
| Magnesium | Low | Very Low| Low | Medium |
| Titanium | High | Low | Very High | Very High|
## How to choose
- Is weight the top priority? → 7616.10,7616.99 (Aluminium) or 8108.90 (Titanium)
- Is corrosion resistance critical? → 7508.90 (Nickel) or 8108.90 (Titanium)
- Is maximum strength needed? → 7318.2X (Steel) or 8101.99 (Tungsten)
- Is the environment explosive or sensitive to sparks? → 7415.33 (Copper)
## Overlaps & pitfalls
- **Overlaps:** Titanium and aluminium both offer good strength-to-weight ratios; steel and tungsten both high strength.
- **Pitfalls:** Zinc, magnesium, and molybdenum are unsuitable for safety carabiners due to low strength or safety risks (e.g., flammability).
- **Note:** If no user context is given, **do not recommend**—choose based on the product’s primary function: use **7616.10,7616.99 (Aluminium)** for sport climbing, **7318.2X (Steel)** for industrial use, or **8108.90 (Titanium)** for premium performance