SAR Class 16E 858 (4-6-2) driver. The centre set of the locomotive's 6 feet diameter driving wheels are flangeless and have wider treads than the other two sets to prevent them from slipping off the rails in sharp curves. The turning mechanisms for the poppet valve gear are mounted on these wheels and the drive shafts that turn the camshafts of the valves are no different from those found under most rear wheel drive cars and trucks. "Location:" Beaconsfield, Kimberley, Northern Cape