The United States Army divides supplies into ten numerically identifiable classes of supply. The North Atlantic Treaty Organisation uses only the first five, for which NATO allies have agreed to share a common nomenclature with each other based on a NATO Standardization Agreement. A common naming convention is reflective of the necessity for interoperability and mutual logistical support.
Class I - Rations - Subsistence, gratuitous health and comfort items.
Class II - Clothing And Equipment - individual equipment, tentage, some aerial delivery equipment, organizational tool sets and kits, hand tools, unclassified maps, administrative and housekeeping supplies and equipment.
Class III - POL - Petroleum, Oil and Lubricants : Petroleum, fuels, lubricants, hydraulic and insulating oils, preservatives, liquids and gases, bulk chemical products, coolants, deicer and antifreeze compounds, components, and additives of petroleum and chemical products, and coal.
Class IV - Construction materials, including installed equipment and all fortification and barrier materials.
Class V - Ammunition of all types, bombs, explosives, mines, fuses, detonators, pyrotechnics, missiles, rockets, propellants, and associated items.
Class VI - Personal demand items.
Class VII - Major end items such as launchers, tanks, mobile machine shops, some parachute systems and vehicles.
Class VIII - Medical material including repair parts peculiar to medical equipment..
Class IX - Repair parts and components to include kits, assemblies, and subassemblies required for maintenance support of all equipment.
Class X - Material to support nonmilitary programs such as agriculture and economic development.
Miscellaneous - Water, salvage, and captured material.
Class I - Items of subsistence, e.g., food and forage, which are consumed by personnel or animals at an approximately uniform rate, irrespective of local changes in combat or terrain conditions.
Class II - Supplies for which allowances are established by tables of organization and equipment, e.g., clothing, weapons, tools, spare parts, vehicles.
Class III - Petroleum, oil and lubricants for all purposes, except for operating aircraft or for use in weapons such as flamethrowers, e.g., gasoline, fuel oil, greases, coal, and coke.
Class IV - Supplies for which initial issue allowances are not prescribed by approved issue tables. Normally includes fortification and construction materials, as well as additional quantities of items identical to those authorized for initial issue such as additional vehicles.
Class V - Ammunition, explosives, and chemical agents of all types.