Postal import and export rules: customs entry by postal presentation fixes duty date and mandates declaration-based assessment. Customs clearance for postal consignments is governed by the Customs Act and postal parcel rules; presentation of the postal Parcel/Letter Mail list to the Proper Officer constitutes the entry and fixes the relevant date for duty and valuation. Declarations on parcels serve as the entry for assessment; detained or suspected consignments are examined, adjudicated and duties are assessed by Customs Appraisers and collected by the Post Office at delivery. Special admissibility, exemption and procedural rules apply to gifts, samples, currency and drawback claims on exports and re-exports by post.