What's the difference between a part, revision, and unit?
Updated July 7, 2026
A part is the product or component family that units belong to (e.g. PCB-V1). A revision is a version of a part; it defaults to A. A unit is the individual physical item under test, identified by a serial number and belonging to one part-and-revision combination. Batches are an optional layer grouping units made in the same lot. The model maps to PLM and ERP item masters.
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