The Model H was introduced by Triumph Motorcycles in 1914. It featured a 550cc single-cylinder engine, a 3 speed manual transmission with a Sturmey-Archer rear hub and a tubular rocking fork frame. Its first version was known simply as the 4hp, while in 1915 the Model H was introduced, optimized for military use during the First World War, with a reinforced gearbox and kick start. This bike was widely used in both civilian and military versions, representing a milestone in the evolution of Triumph due to its greater power, reliability, and mechanical improvements over its predecessors, and laying the foundation for the brand's future models. It has evolved to different versions sucha es the 3T and 3TA up to the 1950´s.