Units and catalogue notation
How to read mL, µL and a nominal volume without turning the page into a method.
Sable Peptides editorial · Reviewed 2026-09-22 · Next review 2027-03-21
Nominal means named
A “2 mL vial” is named for a nominal volume. It is not a promise that the vial delivers 2.000 mL, and it is not a volumetric flask. Graduations on a serological pipette are described the same way: nominal.
Prefixes you will see
mL is millilitre. µL is microlitre. A 200 µL tip is a tip sold for that nominal range. M, where it appears on a reagent label such as “1 M”, is the supply label’s concentration statement. Sable Peptides has not assayed it. The page will say that.
What this page is not
It is not a method, a dilution series or a calculation for preparing a dose. The International System of Units is maintained by the Bureau International des Poids et Mesures. This page is a reading aid for the catalogue, not a copy of the SI Brochure.
The BIPM publishes the SI at bipm.org.
Sources. The SI is published by the BIPM (bipm.org). This page is a plain-language reading aid, not a reproduction of the SI Brochure.
Related notes
- Certificates, and what “not on file” meansA certificate of analysis is a document about a lot. If we do not have the document, we do not invent the numbers that would have been on it.
- How an order worksThe path from a variant to a confirmation screen, and the steps that are deliberately not live.
- How to read a catalogue recordEvery public product page is built from the same fields. If a field is empty, the page says so.