Propeller shafts, also known as driveshafts, transmit rotational power from the transmission or transfer case to the driving axle(s) in rear-wheel-drive, all-wheel-drive, and four-wheel-drive vehicles. These tubular shafts utilize universal joints or constant-velocity joints at each end to accommodate changes in angle and maintain torque transfer. Shafts are typically constructed from steel or aluminum alloy for strength and weight optimization. Balancing is critical to minimize vibration at operating speeds. Some designs incorporate a slip yoke to allow for suspension articulation and driveline movement.