The DUKW (colloquially known as Duck) is a six-wheel-drive amphibious truck that was designed by a partnership under military auspices of Sparkman & Stephens and General Motors Corporation (GMC) during World War II for transporting goods and troops over land and water and for use approaching and crossing beaches in amphibious attacks. Designed only to last long enough to meet the demands of combat, mass produced Ducks, a modification of the 2-ton capacity "deuce" trucks used by the U.S. military in World War II, were later used as tourist craft in marine environments.