Category Nuances for serial_number:

• individual,
• digital,
• unique,
• identifiable,
• essential,
• replaceable,
• musical,
• military,
• stock,
• physical,
• key,
• secondary,
• central,
• dynamic,
• mechanical,
• ancillary,
• permanent,
• variable,
• standard,

Simple Categories for serial_number:

• identifier,
• work,
• document,
• id,
• unit,
• attribute,
• item,
• mark,
• identification,
• marking,
• signal,
• property,
• data,