## Common ground
All options describe book carts—mobile storage units for books—classified by their primary material.
## Options at a glance
**9403.20 – Base metal**
- **Defining trait:** Constructed primarily from steel, iron, or other non-wood, non-plastic metals.
- **Typical examples:** Steel shelving carts with metal frames and wheels.
- **Best fit when:** The cart has a strong, durable metal frame and is used in high-traffic library or industrial settings.
**9403.30 – Wood**
- **Defining trait:** Made primarily from solid wood or wood-based panels (e.g., plywood).
- **Typical examples:** Wooden book carts with wooden shelves and joints.
- **Best fit when:** The cart has a traditional, natural look and is made from timber or engineered wood.
**9403.70 – Plastic material**
- **Defining trait:** Constructed mainly from molded or extruded plastic (e.g., polypropylene, HDPE).
- **Typical examples:** Lightweight, stackable plastic carts used in schools or offices.
- **Best fit when:** The cart is lightweight, often color-coded, and designed for easy cleaning.
**9403.82 – Bamboo**
- **Defining trait:** Made primarily from bamboo, a fast-growing grass used as a sustainable wood substitute.
- **Typical examples:** Eco-friendly book carts with bamboo frames or shelves.
- **Best fit when:** The cart emphasizes sustainability and natural aesthetics.
**9403.83 – Rattan**
- **Defining trait:** Constructed from woven rattan, a tropical palm fiber used in furniture.
- **Typical examples:** Decorative book carts with wicker-style baskets or frames.
- **Best fit when:** The cart has a handcrafted, woven appearance and is used in aesthetic or boutique settings.
**9403.89 – Other materials (cane, osier, etc.)**
- **Defining trait:** Made from natural fibers like cane, osier (willow), or similar pliable plant materials.
- **Typical examples:** Woven baskets on wheels, rustic-style carts.
- **Best fit when:** The cart uses non-wood, non-plastic, non-bamboo natural fibers in a woven structure.
## Key differences
| Material | Frame/Structure Type | Durability | Aesthetic | Sustainability |
|----------------|------------------------|------------|-----------|----------------|
| Base metal | Rigid, welded | High | Industrial | Medium |
| Wood | Solid or panel | Medium | Classic | Low to medium |
| Plastic | Molded or extruded | Low to medium | Modern | Low |
| Bamboo | Solid or laminated | High | Natural | High |
| Rattan | Woven | Low | Crafted | High |
| Other fibers | Woven (cane/osier) | Low | Rustic | High |
## How to choose
- Is the cart made mostly of steel or iron? → 9403.20
- Is it primarily wood (solid or panel)? → 9403.30
- Is it molded plastic, lightweight, and stackable? → 9403.70
- Is it made from bamboo with a natural grain? → 9403.82
- Is it woven from rattan or similar palm fiber? → 9403.83
- Is it made from cane, willow, or other pliable plant fibers? → 9403.89
## Overlaps & pitfalls
A cart with a bamboo frame and rattan shelves could fit both 9403.82 and 9403.83. Similarly, “other materials” may overlap with bamboo or rattan if not clearly defined. **No priority rule is specified**—choose based on the product’s MAIN material. If uncertain, use the dominant structural component