The compressor is made up of an impeller, a diffuser and a volute housing. These included rubber-bushed tracks, rear mounted radial engines and the vertical volute spring suspension. It is the first known volute krater made of clay. Such a design includes the volute siphon. A volute spring is a compression spring in the form of a cone (a volute). Friction and flow separation losses also occur due the volute passage. Some terminate with convex volute ends, while others have double convex volute ends. It had bogie suspension for the wheels and vertical volute springs for the tracks. The vertical volute spring suspension system is a type of vehicle suspension system. The front suspension uses leaf springs, while the tracks use vertical volute springs. The capital features a volute, an ornament shaped like a scroll, at the four corners. In late 1969, a reinforcing neck volute was added. In 1981, the volute was phased out.