16 CFR 503.4 - Net quantity of contents, numerical count.
(a) When a consumer commodity is properly measured in terms of count only, or in terms of count and weight, volume, area, or dimension, the regulations are interpreted not to require the declaration of the net content as “one”, provided the statement of identity clearly expresses the fact that only one unit is contained in the package. Thus the unit synthetic sponge, the unit light bulb, and the unit dry cell battery do not require a net quantity statement of “one sponge,” “one light bulb,” or “one dry cell battery.” However, there still exists the necessity to provide a net quantity statement to specify weight, volume, area, or dimensions when such are required. For example, the synthetic sponge which is packaged, requires dimensions such as “5 in. × 3 in. × 1 in.” A multicomponent package or a package containing two or more units of the same commodity shall bear the net quantity statement in terms of count, and weight, volume, area, or dimensions as required. This interpretation does not preclude the option to enumerate a unit count on a single packaged commodity if so desired.