Here is a quick guide to decoding government contract dates on your clothing and equipment marked with DA, DSA, DLA, and SPO contracts.

One of the most commonly encountered features on United States Military Equipment and Clothing is a DA, DSA, DLA, or SPO contract number.  If you can correctly read the stamp, you will know when your collectable was manufactured which can significant aid in determining the value of your item!

1. The earliest code used was "DA" which stands for Defense Agency.  It was used from from 1953 to 1961.  Look for a two digit number, typically near the end of the code (it will range from 53 to 61) for the year of manufacture of your item. 

2. The DSA, Defense Supply Agency, was used from 1962 to 1977.   DSA stamped items introduced a systematic dating process and is as follows:

1962 thru 1964 – Prefix of DSA-1, Suffix of E6Y (Y=Year)
1965 – Prefix of DSA-1, No Dating Suffix
1966 – Prefix of DSA-100, No Dating Suffix
1967 thru 1977 Prefix of DSA-100, Dating Suffix of YYM (YY=Year, M=Month)

After the DSA Prefix and before the Dating Suffix, if applicable, there may appear additional numeric or alphanumeric codes.  These codes have nothing to do with date of manufacture, but relate either the Defense contract, or a Manufacturer’s code.

3. The DLA, the Defense Logistics Agency was in use from 1978 to 1993.  The DLA dating system, substituted DLA for DSA; for example: DLA-100-805 would indicate an item made in May of 1980.

From 1994 to the present, the SPO – System Program Offices have been in charge of procurements.  The SPO stamp has the year of manufacture as the first two number code following the initial 6 character alphanumeric code; ie: XYZ23A-05-xxxx would indicate an item made in 2005.

If your item has a Manufacture’s Stamp only – it was made prior to the beginning of the Korean War.  A knowledge of when the particular item was used will narrow down the time frame.  A date stamp may, or may not be present.

The Federal Stock Number (FSN) was an 11 digit codification system used by the U.S. federal government from 1955 to 1974.  The first four digits were the Federal Supply Classification Group which relates the item to the Federal Supply Group and Federal Supply Classification.  The next seven digits were the unique item's serial number, or Federal Item Identification Number (FIIN).

The Federal Stock Number was officially replaced by the National Stock Number (NSN) beginning on September 30, 1974.