A batch number ties the vial in a buyer's hand to the lab report for that production run. It belongs on the label, the product page, the lab report and the order record.
Without it, a lab report proves nothing about any particular vial.
Batch number
The code that identifies every vial made in the same production run.
See it running on your own catalog
Purity does the work these terms describe: batches held until their lab report is in, payments matched to orders, and wording checked before it sends.