Amphibious 2 ½ ton Truck; pronounced 'duck', the DUKW usually carried supplies.

An amphibious 2 1/2 ton utility truck used to deliver supplies, ammunition, and weapons from ship to shore. Pronounced "duck," the acronym reflects the date it entered the inventory (D[ate]: 1942); the kind of vehicle it is (U[tility], amphib.); its forward drive (K or front-wheel drive); and its rear drive (W or two rear driving axles).

An amphibious truck used by the Allies

The DUKW (popularly pronounced DUCK) is a six-wheel-drive amphibious truck that was originally designed inside General Motors Corporation during World War II for transporting goods and troops over land and water and for use approaching and crossing beaches in amphibious attacks.