Perimeter frame rails and door frames rails are described for a more thermally efficient and cost-effective display case such as for refrigerated display cases. A plurality of glyphs to be rendered are received. A tensioning cord is operatively coupled between the roller tube and a second fabric end opposite the first fabric end, and is windingly received about the roller tube. The soy based component can be soy flour or soy protein. The gain stage adjusts the gain of the feedforward equalizer by adjusting the amplitude of the filtered signal.