The GMC CCKW, also known as "Jimmy", or the G-508 by its Ordnance Supply catalogue number, was a highly successful series of off-road capable, 2​1⁄2-ton, 6x6 trucks, built in large numbers to a standardized design (from 1941 to 1945) for the U.S. Army, that saw heavy service, predominantly as cargo trucks, in both World War II and the Korean War.
 
The original "Deuce and a Half", it formed the backbone of the famed Red Ball Express that kept Allied armies supplied as they pushed eastward after the Normandy invasion. The CCKW came in many variants, including open or closed cab, long wheelbase (LWB) CCKW-353 and short (SWB) CCKW-352, and over a score of specialized models, but the bulk were standard, general purpose, cargo models. A large minority were built with a front mounted winch, and one in four of the cabs had a machine-gun mounting ring above the co-driver's position.
 
Of the almost 2.4 million trucks that the U.S. Army bought between 1939 and December 1945, across all payload weight classes, some 812,000, or just over one third, were ​2 1⁄2-ton trucks.