## Common ground
All options refer to chain links made from different metals, used for connecting components in mechanical or structural applications.
## Options at a glance
**7315.8X – Iron or steel**
- **Defining trait:** Made from iron or steel, offering high tensile strength and durability.
- **Typical examples:** Industrial conveyor chains, bicycle chains, anchor chains.
- **Best fit when:** Strength and load-bearing capacity are critical.
**7419 – Copper**
- **Defining trait:** Made from copper, known for excellent electrical conductivity and corrosion resistance.
- **Typical examples:** Electrical grounding links, decorative chains in marine environments.
- **Best fit when:** Conductivity or resistance to corrosion in wet/salty conditions is needed.
**7616.9X – Aluminium**
- **Defining trait:** Made from aluminium, lightweight and resistant to rust.
- **Typical examples:** Lightweight suspension systems, decorative outdoor chains, aerospace components.
- **Best fit when:** Weight reduction is important and high strength is not required.
## Key differences
| Feature | Iron/Steel (7315.8X) | Copper (7419) | Aluminium (7616.9X) |
|------------------|------------------------|--------------------|------------------------|
| Strength | Very high | Low to moderate | Moderate |
| Weight | Heavy | Medium | Light |
| Corrosion resistance | Poor (rusts) | Excellent | Excellent |
| Electrical use | Not suitable | Ideal | Not ideal |
## How to choose
- Is the chain used in high-load or heavy-duty applications? → 7315.8X
- Does it need to conduct electricity or resist saltwater corrosion? → 7419
- Is weight a major concern, and is strength less critical? → 7616.9X
## Overlaps & pitfalls
A chain could be made of copper-coated steel (e.g., for conductivity + strength), but the primary material determines classification. If a product combines traits (e.g., light and conductive), prioritize based on **main function**: mechanical connection vs. electrical use. No option is inherently more accurate—choose by dominant purpose