NEMA reaffirmed ANSI C78.20-2003 American National Standard for Electric Lamps—A, G, PS, and Similar Shapes with E26 Medium Screw Bases. Standard sets forth physical and electrical characteristics of the group of incandescent lamps that have A, G, PS, and similar bulb shapes with E26 single- and double-contact medium screw bases, including reduced-wattage versions. Last reaffirmed in 2007, standard was developed by ANSI Accredited Standards Committee for Electric Lamps.