Although common in America, where several makers offered similar units including the "Tree" from Racine, the Marvin from Michigan, the "Halco" from Detroit and Kearney & Trecker with their Dalrae-manufactured "Midgetmill" and "Speedmill", they were not so widely employed in the United Kingdom. However, by the late 1940s, the Bristol-manufactured Cowards was being listed, its fitting allowing any ordinary round-overarm horizontal miller (of which many thousands were still in use) to be converted economically into a much more versatile vertical machine.