## Common ground
All options are threaded articles (e.g., bolts, nuts, screws) made from different metallic materials.
## Options at a glance
**7318.1X – Iron or steel**
- **Defining trait:** Made from iron or steel; most common and cost-effective material.
- **Typical examples:** Standard bolts, machine screws, threaded rods.
- **Best fit when:** General-purpose use, high strength, or low cost is key.
**7415.33 – Copper**
- **Defining trait:** Made from copper; excellent electrical and thermal conductivity.
- **Typical examples:** Electrical connectors, specialized fasteners in electronics.
- **Best fit when:** Conductivity matters more than mechanical strength.
**7508.90 – Nickel**
- **Defining trait:** Made from nickel; resists corrosion and high temperatures.
- **Typical examples:** Fasteners in aerospace or chemical environments.
- **Best fit when:** Corrosion resistance or heat stability is required.
**7616.10 – Aluminium**
- **Defining trait:** Made from aluminium; lightweight with moderate strength.
- **Typical examples:** Aircraft components, consumer electronics.
- **Best fit when:** Weight reduction is critical.
**7907.00 – Zinc**
- **Defining trait:** Made from zinc; often used for galvanizing or sacrificial coatings.
- **Typical examples:** Zinc-coated bolts (not pure zinc threaded parts).
- **Best fit when:** Corrosion protection via coating, not structural use.
**8101.99 – Tungsten**
- **Defining trait:** Made from tungsten; extremely high melting point and hardness.
- **Typical examples:** Specialized fasteners in extreme heat (e.g., furnaces).
- **Best fit when:** High-temperature or wear resistance is essential.
**8102.99 – Molybdenum**
- **Defining trait:** Made from molybdenum; high strength at elevated temperatures.
- **Typical examples:** Fasteners in aerospace or industrial heating systems.
- **Best fit when:** High-temperature performance with good creep resistance.
**8104.90 – Magnesium**
- **Defining trait:** Made from magnesium; very light but reactive and flammable.
- **Typical examples:** Lightweight fasteners in defense or aerospace (rare).
- **Best fit when:** Extreme weight savings needed, with controlled environment.
**8108.90 – Titanium**
- **Defining trait:** Made from titanium; high strength-to-weight ratio and corrosion resistance.
- **Typical examples:** High-performance bolts in aviation or medical implants.
- **Best fit when:** Strength, lightness, and corrosion resistance are all needed.
## Key differences
| HS Code | Material | Key Property | Typical Use Case |
|--------|----------------|----------------------------|--------------------------|
| 7318.1X | Iron/Steel | High strength, low cost | General engineering |
| 7415.33 | Copper | Conductivity | Electrical applications |
| 7508.90 | Nickel | Corrosion & heat resistance| Harsh environments |
| 7616.10 | Aluminium | Lightweight | Aerospace, electronics |
| 7907.00 | Zinc | Coating material | Galvanized fasteners |
| 8101.99 | Tungsten | Extreme heat resistance | High-temp industrial |
| 8102.99 | Molybdenum | Creep resistance | High-temp structural |
| 8104.90 | Magnesium | Very light, reactive | Specialized lightweight |
| 8108.90 | Titanium | Strength-to-weight + corrosion | Premium applications |
## How to choose
- Is the product used in high heat or extreme environments? → 8101.99, 8102.99
- Does weight matter most? → 7616.10, 8104.90
- Is electrical conductivity needed? → 7415.33
- Is corrosion resistance critical? → 7508.90, 8108.90
- Is it a standard, general-purpose fastener? → 7318.1X
## Overlaps & pitfalls
- Zinc (7907.00) is rarely used for pure threaded articles; most are coated.
- Titanium and nickel both resist corrosion—choose based on weight/strength needs.
- Tungsten and molybdenum are similar in high-temp use but differ in strength and cost.
- No clear priority: choose based on the product’s **main function** (e.g., structural, conductive, lightweight)