Know More About NSN:
A NATO Stock Number, or National Stock Number (NSN) as it is known in the US, is a 13-digit numeric code, identifying all the 'standardized material items of supply' as they have been recognized by all NATO countries including United States Department of Defense. Pursuant to the NATO Standardization Agreements, the NSN has come to be used in all treaty countries, where it is also known as a NATO Stock Number. However, many countries that use the NSN program are not members of NATO, e.g. Japan, Australia and New Zealand. A two-digit Material Management Aggregation Code (MMAC) suffix may also be appended (see ), to denote asset end use but it is not considered part of the NSN. An item having an NSN is said to be "stock-listed".
Each element, a through m, was originally intended to be a single decimal digit. As inventories grew in complexity, element g became alphanumeric, beginning with capital A for certain newly added items. By 2000, uppercase C was in use.
Federal Supply Class: The initial subgroup, abcd, is the Federal Supply Class (FSC)
or National Supply Classification (NSC). In theory, similar items would always have closely related numbers in this section of the NSN, no matter how the section is referred to. As the number of items has steadily increased and the system has become more complicated, it has not always been possible to keep similarity in numbers when the items are similar.
National Item Identification Number: National (or NATO) Item Identification Number (NIIN) is a 9-digit numeric code which uniquely identifies an item of supply in the NATO Codification System (NCS).
National Codification Bureau: The ef pair is used to record which country was the first to codify the item—which one first recognized it as an important item of supply. This is generally the country of origin, meaning the country of final manufacture. The formal name of the field is CC for Country Code or NCB, because NCB also stands for National Codification Bureau. According to this system, for example, US is 00 and 01, Japan 30, Saudi Arabia 70, the UK is 99 and Australia is 66.
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. Items predating roughly 1975 in warehouses are frequently stenciled with FSNs. The FSN system originated in the US Department of War before or during the Second World War. As of 1998, the system was at least principally administered by the Defense Logistics Agency within the U.S. Department of Defense.
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.
Federal Stock Number
A Federal Stock Number (or FSN) was an 11-digit numeric code used to identify items contained within the Joint Army-Navy Catalog System. The Federal Stock Number was used from 1949 to 1975 when it was replaced by the National Stock Number. The conversion from FSN to NSN was typically done by adding "00" between the first set of numbers (the Federal Supply Class, or FSC) and the second set of numbers. For example, the FSN: 3139-121-6210 would become 3139-00-121-6210.