541 Subfield $o - Type of unit:

Subfield $o contains the type of unit, defined as the name of the unit of measurement.

If subfields $n and $o are repeated in one 541 field, each subfield $o follows its associated subfield $n.

Example:

541 ##$aSparkling Brew Beer Company;$bNew Hops Road, Port Washington, WI 53074;$e1987-1;$n4$orecord center cartons;$n2$oreels of microfilm;$d1987/01/02.