Vintage Mobil Gasoline Porcelain Sign. This vintage porcelain sign features the motorcycle biker on the West coast riding over a bridge. The sign measures 11 3/4 inches and has a colorful design with excellent porcelain. It is a great piece of gas and oil advertising memorabilia for collectors, retro man cave decor or your shop or garage. Collectors of vintage gas and oil advertising signs, as well as fans of Nostalgic man cave themes, will appreciate this amazing find. Vintage Mobil Gasoline porcelain sign. 11 3/4 inches in diameter. Vibrant colors and excellent porcelain.