NATO Stock Number

A two-digit Material Management Aggregation Code (MMAC) suffix may also be appended,[1] to denote asset end use but it is not considered part of the NSN.

In Spanish-speaking countries it is known as a Número Nacional de Efecto (NNE), or "National Item Number".

As inventories grew in complexity, element g became alphanumeric, beginning with uppercase A for certain newly added items.

The first two digits of the NIIN (the ef pair) are used to record which country was the first to codify the item—which one first recognized it as an important item of supply.

[2] The NCB is the organisation, typically a government agency, in charge of maintaining the NCS database within a given country.

The first countries to receive NCB code numbers were the United Kingdom (99), Australia (66), and New Zealand (98)—as they had already been involved in the program.

NATO was assigned the NCB code (11) for its items as it was the next number available after the 00 to 10 block set aside for the United States' own use.

All of Luxembourg's transactions are catalogued by Belgium (13) and Iceland uses other nations' NSNs when they make or order any stock items.

For instance, the experimental 5.56×45mm NSWC Crane Close Quarters Battle Receiver was originally codified as 1005-LL-L99-5996.

A six-position alphanumeric code assigned by the Army Materiel Command that identifies the generic nomenclature of specific types of equipment.

Example: Amalgamated Bio-Carbon (manufacturer code ABC) makes a batch of 40mm grenade shells in January, 2000.

The NSN is an expanded version of the older Federal Stock Number (FSN), which lacked the national-origin code labeled ef above, in the second subgroup.

Other stock numbering systems are in use within the US DoD, but as of 2005, the NSN remained the most common and least ambiguous way to identify most standardized items of supply.

On July 7, 1952 Public Law 82-436 (Defense Cataloging and Standardization Act) was passed by the second session of the 82nd Congress.

It authorized the FSN to replace the Ammunition Identification Code (AIC) and Ordnance Stock Number (OSN).

These include Electronic Components, Medical Equipment, Office Furniture, Food items, Clothing, Industrial goods (pumps, valves, motors ...) and all kinds of Fasteners (bolts, nails, rivets ...), to name a few.

For this reason, catalogs have a broader appeal, beyond their original audience (Defense agencies and their direct contractors.)