Appointment of customs officers designates additional and assistant collectors for specified districts under statutory customs authority. Under section 4(1) of the Customs Act, 1962 the Central Government appoints the Additional Collector, Preventive Unit, Jodhpur and specified Assistant Collectors of Customs, assigning them preventive jurisdiction over listed districts by reference to a Table that pairs each district or tehsil with the designated Preventive Unit post, thereby allocating territorial enforcement responsibility among Jodhpur, Bikaner, Barmer, Jaisalmer and Sri Ganganagar units.