(1) Class 1. Premises that may be owned or leased by the Government, when the exigencies of the service as determined by the port director so require, and used for the storage of merchandise undergoing examination by Customs, under seizure, or pending final release from Customs custody. Merchandise will be stored in such premises only at Customs direction and will be held under “general order.”

(2) Class 2. Importers' private bonded warehouses used exclusively for the storage of merchandise belonging or consigned to the proprietor thereof. A warehouse of class 4 or 5 may be bonded exclusively for the storage of goods imported by the proprietor thereof, in which case it shall be known as a private bonded warehouse.

(3) Class 3. Public bonded warehouses used exclusively for the storage of imported merchandise.

(4) Class 4. Bonded yards or sheds for the storage of heavy and bulky imported merchandise; stables, feeding pens, corrals, or other similar buildings or limited enclosures for the storage of imported animals; and tanks for the storage of imported liquid merchandise in bulk. If the port director deems it necessary, the yards shall be enclosed by substantial fences with entrances and exit gates capable of being secured by the proprietor's locks. The inlets and outlets to tanks shall be secured by means of seals or the proprietor's locks.

(5) Class 5. Bonded bins or parts of buildings or of elevators to be used for the storage of grain. The bonded portions shall be effectively separated from the rest of the building.

(6) Class 6. Warehouses for the manufacture in bond, solely for exportation, of articles made in whole or in part of imported materials or of materials subject to internal-revenue tax; and for the manufacture for home consumption or exportation of cigars in whole of tobacco imported from one country.

(7) Class 7. Warehouses bonded for smelting and refining imported metal-bearing materials for exportation or domestic consumption.

(8) Class 8. Bonded warehouses established for the purpose of cleaning, sorting, repacking, or otherwise changing in condition, but not manufacturing, imported merchandise, under Customs supervision and at the expense of the proprietor.

(9) Class 9. Bonded warehouse, known as “duty-free stores”, used for selling, for use outside the Customs territory, conditionally duty-free merchandise owned or sold by the proprietor and delivered from the Class 9 warehouse to an airport or other exit point for exportation by, or on behalf of, individuals departing from the Customs territory for destinations other than foreign trade zones. Pursuant to 19 U.S.C. 1555(b)(8)(C), “Customs territory”, for purposes of duty-free stores, means the Customs territory of the U.S. as defined in § 101.1(e) of this chapter, and foreign trade zones (see part 146 of this chapter). All distribution warehouses used exclusively to provide individual duty-free sales locations and storage cribs with conditionally duty-free merchandise are also Class 9 warehouses.

(10) [Reserved]

(11) Class 11. Bonded warehouses, known as “general order warehouses,” established for the storage and disposition exclusively of general order merchandise as described in § 127.1 of this chapter.