Heading 4421 is a residual category — it applies only when no other heading in the wood chapter (or elsewhere in the tariff schedule) more specifically describes the article. The correct approach is to work through the more specific headings first: frames (4414), packaging (4415), builders' joinery (4418), tableware (4419), and decorative articles (4420). Only if none of those headings apply does 4421 become the correct classification. A binding ruling from CBP is advisable for novel or borderline products.

Within heading 4421, bamboo articles that are not clothes hangers or coffins fall under 442191 (other bamboo articles NESOI). However, bamboo goods that fit a more specific heading elsewhere in the chapter — such as bamboo kitchenware under 4419 or bamboo builders' joinery under 4418 — are classified there instead. The bamboo subheadings within 4421 are themselves residual, applying only when no other heading covers the article.