M3 half-track

The U.S. M3 series of half-tracked trucks entered service in World War II. Although long out of service in the U.S. armed forces, these half-tracks remain in use in several other countries as armored personnel carriers, mortar carriers, air defense vehicles and support vehicles.

The M3 is a truck with its rear axles replaced by a track system. The track system on each side consists of a front-drive sprocket, rear idler and four small road wheels in a bogie that extends fore and...