A NAICS (North American Industry Classification System) is similar to a NSN, but where an NSN looks at the products, the NAICS looks at industries.
If you are trying to figure out how to use a NATO Stock Number (aka National Stock Number), don’t worry because it’s quite easy. In about three minutes you’ll have it all figured out.
Welcome to the NSN Database (NSNDB.com). This is a site designed around an easy, free-to-use version of the NATO Stock Number (sometimes referred to as the National Stock Number) database.