Customs exemption for aircraft maintenance components with conditional re export and bond obligations, and separate nil duty research equipment exemption. Amendment inserts entry 544A allowing concessional treatment for components and parts listed in OEM manuals when imported for servicing, repair, maintenance or overhauling, and inserts entry 613 granting a time limited nil duty exemption for equipment and buoys for the RAMA programme; Condition 118 requires a Ministry of Earth Sciences certificate and execution of a bond obliging re export within two years (extendable by one year) and payment of integrated tax with interest on breach.