Abstract: Folding booms are attached to a hub and wheel. The drive wheel of an electric motor contacts a plane face of the wheel, and the motor is mounted to move the drive wheel radially over the face of the wheel. Movement of the motor causes change in speed of rotation of the booms, the drive arrangement functioning as a continuously variable transmission. The drive wheel also functions as a clutch to limit the force to be applied to an animal that is being led. To provide clearance for fire equipment and other vehicles, the booms can be folded or raised upwardly about mounting hinges. The force required for folding is applied by a hydraulic jack operating through a central shaft and cables.