NATO Codification System

The NATO Stock Number (NSN) is a 13 digit number and is divided into 3 parts:

• The first part (4 digits) is the NATO Supply Classification Code and relate the item to the group and class of similar items: e.g. 5920: 59 for Electrical and Electronic Equipment Components and 5920 Fuses, Arrestors, Absorbers and Protectors.
   
• The middle part (2 digits) indicates the NCB assigning the NSN:
  Country code: e.g. 00/01 for USA, 12 for Germany, 13 for Belgium, 14 for France, 15 for Italy, 17 for Netherlands, 23 for Greece, 33 for Spain, 66 for Australia, 99 for UK
   
• The final part (7 digits) of the NSN do not have inherent significance. However, the number is assigned to one and to only one Item of supply within the codifying country.

References of listed protectors with a NATO Stock Number