D.U. Manufacturing Co. Ltd., was the second venture of Harold E. Dew, who had made the Dewcar until he left that company in February 1914. Like the Dew, the D. Ultra was a cyclecar, but a more sophisticated design, with water-cooled Charter Lea 8hp V-twin engine, a 4 speed friction transmission and chain drive. It came as a 2-seater or a delivery van. Both Air and water-cooled twins were offered in 1915 and also a four powered by a 10hp water-cooled Lister engine.