This order declares that a specific product — cylinder assemblies for compressed natural gas (CNG) buses, assembled in roof‑mounted frames — is to be treated under Item 50 of Part III of Schedule 4 to the Customs Tariff Act 1995. Mechanically, it changes the tariff treatment that applies to those imported goods from 20 November 2008. Who it affects: importers of these CNG cylinder assemblies, customs officials administering tariffs, and suppliers. It matters because it alters the import tariff outcome (and thus import costs) for that narrowly described product.