Paperwork problems delay shipments more often than production problems do, and almost all of them come down to one thing: a description that does not match what customs sees when the container is opened. Getting classification and documents right before dispatch is far cheaper than fixing them at the port.
How HS Classification Works
The Harmonized System assigns a numeric code to traded goods. The first six digits are internationally harmonised; individual countries then add further digits for their own tariff and statistical purposes. That structure explains the most common surprise: the same product can carry different full codes in different destination markets.
For protective cases, classification depends on material and construction. Moulded plastic cases used as packing containers generally fall within the chapter covering plastics and articles thereof, in the heading for articles for the conveyance or packing of goods. Metal cases, cases fitted with specific equipment, and cases forming part of a larger instrument are classified differently.
Core Documents for a Shipment
| Document | Purpose | Common error |
|---|---|---|
| Commercial invoice | Declares value, description, parties and terms | Vague description; value inconsistent with the contract |
| Packing list | Details cartons, quantities, net and gross weights | Weights or carton counts not matching the shipment |
| Bill of lading / airway bill | Transport contract and receipt | Consignee details inconsistent with the invoice |
| Certificate of origin | Supports preferential duty claims where applicable | Requested after departure rather than before |
| Test or compliance documents | Evidence where the destination requires it | Absent, or not matching the product shipped |
Writing a Description That Survives Inspection
- Name the material — moulded plastic, aluminium, and so on.
- State the function — protective carrying case for equipment.
- Include model and quantity so the line item can be reconciled with the packing list.
- Avoid internal codes that mean nothing to a customs officer.
- Keep it consistent across invoice, packing list and any certificate.
Practical Steps Before Dispatch
Confirm the code with your broker before the first shipment and record it; send draft documents to the consignee for review; and check that wood packaging, where used, meets the treatment and marking requirements covered in our article on export packaging compliance. Finally, keep a copy of every document set — the next shipment is easier when the last one is on file.