Vintage Edison Electric Porcelain Sign. Add some retro charm to your garage or workshop with this vintage. Edison Company porcelain sign. Featuring Reddy Kilowatt, this 11 3/4 sign is a colorful addition to any gas and oil-themed collection. This sign is perfect as a gift or for any auto shop, man cave or gas station and is an excellent way to display this type of advertising. Vintage Reddy Electric porcelain sign. 11 3/4 inches in diameter. Vibrant colors and excellent porcelain.