## Common ground
All options refer to inspection traps made from different metals, used for detecting or capturing objects in industrial or security settings.
## Options at a glance
**7325 – Iron or steel**
- **Defining trait:** High strength and magnetic properties; ideal for heavy-duty use.
- **Typical examples:** Steel grates in conveyor systems, magnetic trap doors.
- **Best fit when:** Durability and magnetism are required (e.g., metal debris detection).
**7508.90 – Nickel**
- **Defining trait:** Corrosion resistance and high-temperature stability; non-magnetic.
- **Typical examples:** Traps in chemical plants, aerospace inspection systems.
- **Best fit when:** Exposure to harsh environments or where magnetic interference must be avoided.
**7616.99 – Aluminium**
- **Defining trait:** Lightweight and non-magnetic; good corrosion resistance.
- **Typical examples:** Traps in food processing, cleanroom inspection systems.
- **Best fit when:** Weight reduction or non-magnetic operation is critical (e.g., electronics).
## Key differences
| Feature | 7325 (Iron/Steel) | 7508.90 (Nickel) | 7616.99 (Aluminium) |
|------------------|-------------------|------------------|---------------------|
| Magnetic? | Yes | No | No |
| Weight | Heavy | Medium | Light |
| Corrosion resistance | Low | Very high | High |
| Typical use | Industrial, rugged | Harsh environments | Clean or sensitive areas |
## How to choose
- Is the trap exposed to chemicals or high heat? → 7508.90
- Does it need to be magnetic? → 7325
- Is weight or non-magnetism critical? → 7616.99
## Overlaps & pitfalls
A trap may fit multiple categories if, for example, it’s made of nickel-coated steel (magnetic but corrosion-resistant). If the material is unclear, prioritize based on the **main functional requirement**: strength (steel), environment (nickel), or sensitivity (aluminium). No option is inherently prioritized—choose by primary use