Broad nexus requirement for TPS imports: imported items must be bona fide inputs used by exporter or supporting manufacturer. TPS duty credit is limited to freely importable inputs, capital goods and specified equipment for the importer or declared supporting manufacturers; imported goods must have a broad nexus with the exported product and be 'used' in its manufacture. SION is prima facie evidence of input status, but exporters may otherwise demonstrate nexus. TPS certificates must endorse supporting manufacturers, and certificates and imported goods are non-transferable and not to be sold. Customs should scrutinize TPS imports for compliance and notify trade.