The Electric Tokamak (ET) was the last of a series of small tokamak machines built in 1998 under the direction of principal investigator and designer, Robert Taylor, a UCLA professor. The machine was designed to be a low field (0.25 T) magnetic confinement fusion device with a large aspect ratio. It is composed of 16 vacuum chambers made of 1-inch thick steel, with a major radius of 5 meters and a minor radius of 1 meter. The ET was the largest tokamak ever built at its time, with a vacuum vessel slightly bigger than that of the Joint European Torus.