These BBL CultureSwab products are packaged in Vi-Pak foil.
Nitrogen gas is injected into both the foil pack and the individual swab packages.
This inner environment works synergistically with sodium thioglycolate in the transport medium to create an ideal Eh potential.
Together, the metallic foil of the outside packaging and the plastic film of the individual swabs block the entry of oxygen and prevent unwanted oxidation of the transport medium.