The "Progress 4WDS" was Kyosho's first electric 4WD off-road racer. The motor was mounted on the rear overhang, and the forward wheel moves with a chain extending from the rear gearbox. This chain system was also tried on the on-road racer, "Fantom EP." The rear suspension was an orthodox double trailing arm and oil damper with coil springs, but the front suspension featured a double wishbone and mono damper, and substituted a torsion bar for a spring. This unique front suspension was rather difficult to set up, and had a short arm, which prevented it from taking powerful strokes.