Two objects can share a model designation while carrying different serial numbers. When recording manufactured equipment, copying only the largest printed number can lose the distinction between a product type and an individual example.
Transcribe the visible labels with their headings and positions. If a number is not identified on the object or in documentation, call it an unidentified marking rather than deciding its role from length alone.
Make the record explicit
For an imagined device, a label might show model A20 and serial 004817. Preserve the leading zeroes in the serial field. They are part of an identifier, not a quantity to simplify.
Check the manufacturer’s documentation or collection catalogue before using a serial sequence to propose a production date. Numbering conventions differ, and a plausible-looking online list may not cover the exact product.
An institution’s accession number belongs in another field again. It identifies the collection record and should not be merged with the manufacturer’s marks.
For publicly shared records, consider whether an identifier creates a privacy or security concern for equipment still in use. A research note can preserve full detail privately while a public description explains the distinction without exposing unnecessary identifying information.
Editorial illustration from this site’s image library; not documentary evidence of the example or object discussed.