Retailers using the Flexis Oxygen Valve receive their products in individual trays, each covered with a clear high-barrier lidding film equipped with the two-part valve. The valve’s upper layer can be clear or printed. When that layer is peeled away, it reveals a second, permeable layer that permits the entry of oxygen. Once the top layer is removed it does not require the entire package to be relabeled. The method allows retailers to pick for the display case any number of packages that arrived in a shipment.