phosphorous gases that add a colorful glow to the electric arcs. Color codes are created listing glass color first, phosphor color second. Example: a code of BB tells you the Electra® Lamp has blue glass with blue phosphor. Note: Red glass color may vary from dark red to orange. When all RR Electra® Lamps are turned on you will see an even red color. 6" W. x 9.5" H.