FSG 48 valves
The Defense Logistics Agency developed and adopted the Federal Supply Classification System. National Stock Numbers are 13-digit numeric codes assigned to all items that are procured, stocked, and distributed by the federal supply chain.
The first four digits of the NSN are known as the Federal Supply Classification Group. This code is further broken down into the Federal Supply Group (FSG) and the Federal Supply Classification (FSC). The FSG is made up of the first two digits of the NSN and the FSC is the second 2-digits of the NSN.
The remaining 9-digits of the NSN are known as the National Item Identification Number. The first two digits of this number are known as the country identifier.
Federal Supply Group 48 category includes products such as electric motor operated valves, hydraulic operated valves, and solenoid operated valves. Federal Supply Group 48 is subdivided into the following classes: