A specific item in a catalog or inventory system for manufacturing or retail.
A reference to a specific area (like a zip code variant) or a case file number.
To make sure I'm writing the right kind of "feature" for you, could you clarify what it refers to? It sounds like it could be one of a few things:
Could you let me know or what industry it belongs to? Once I have that context, I can put together a proper feature highlighting its specs, importance, or usage for you.