Use of resin instead of steel and glass materials in automobiles is an environmental technology that has been used to reduce weight and lower fuel consumption, resulting in lower CO₂ emissions. To produce the resin parts, electric injection molding machines, which use less energy, compared with traditional machines, and no hydraulic oil have been promoted since the 1990s. Improvements in the productivity of moldings, including thin-wall moldings that contribute to a reduced number of molding cycles and lighter products (due to the reduced amount of resin), have sometimes been inconsistent with energy conservation principles, because sudden accelerations, decelerations, and quick operations are required to produce them, so that high-power, high-speed injection molding machines are required. Mitsubishi Heavy Industries (MHI), Ltd., has developed the "em Ⅱ" series, which consists of two-platen large electric injection molding machines featuring high throughput and high-speed injection. These machines permit downsizing, and small footprint, energy, and resources (hydraulic oil), thereby reducing their environmental burden. Features of these machines are discussed below.