## Common ground
All options are ear plugs, designed to reduce sound exposure by blocking noise entering the ear canal.
## Options at a glance
**3926.90 – Made of plastic material**
- **Defining trait:** Constructed primarily from synthetic plastic (e.g., polyethylene or PVC).
- **Typical examples:** Disposable foam-plastic hybrid plugs, molded plastic ear tips.
- **Best fit when:** The product is rigid, lightweight, or has a molded shape with a plastic shell.
**4016.99 – Made of rubber**
- **Defining trait:** Manufactured from natural or synthetic rubber (e.g., latex or silicone).
- **Typical examples:** Reusable rubber ear plugs, custom-fitted silicone molds.
- **Best fit when:** The product is soft, flexible, and designed for repeated use with a rubbery texture.
## Key differences
| Feature | 3926.90 (Plastic) | 4016.99 (Rubber) |
|---------------------|--------------------------|----------------------------|
| Material flexibility| Rigid or semi-rigid | Soft and flexible |
| Reusability | Usually disposable | Often reusable |
| Common form | Molded or pre-shaped | Elastomeric, stretchable |
## How to choose
- Is the plug made of a hard or rigid plastic? → 3926.90
- Does it feel soft and stretchy like rubber or silicone? → 4016.99
## Overlaps & pitfalls
Some ear plugs use both materials (e.g., a plastic shell with a rubber tip), which could create ambiguity. If the product is primarily plastic, use 3926.90; if rubber dominates in form and function, use 4016.99. The main material determines the classification—do not prioritize shape or use over material composition