use a single Jeep component and was slightly shorter than its American inspiration, but wider, heavier, faster and still retained the PTO drives. The Land Rover was designed to only be in production for two or three years to gain some cash flow and export orders for the Rover Company so it could restart up-market car production. Once car production restarted, however, it was greatly outsold by the off-road Land Rover, which developed into its own brand that remains successful today. Many of the defining and successful features of the Land Rover design were in fact the result of Rover's drive to simplify the tooling required for the vehicle and to use the minimum amount of rationed materials. As well as the aluminium alloy bodywork (which has been retained throughout production despite it now being more expensive than a conventional steel body due to its ideal properties of light weight and corrosion resistance) other examples include the distinctive flat body panels with only simple, constant-radius curves (originally used because they could be cut and formed by hand from aluminium sheet on a basic jig) and the sturdy box-section ladder chassis, which on series vehicles was made up from four strips of steel welded at each side to form a box, thus cutting down on the complex operations required when making a more conventional U- or I-section frame. Series I Land Rover entered production in 1948 with what has later been termed the Series I. This was launched at the Amsterdam Motor Show. It was designed for farm and light industrial use, with a steel box-section chassis and an aluminium body. Originally the Land Rover was a single model offering, which from 1948 until 1951 used an wheelbase and a 1.6-litre petrol engine producing around . The four-speed gearbox from the Rover P3 was used, with a new two-speed transfer box. This incorporated an unusual four-wheel-drive system, with a freewheel unit (as used on several Rover cars of the time). This disengaged the front axle from the manual transmission on the overrun, allowing a form of non- permanent 4WD. A ring-pull mechanism in the driver's footwell allowed the freewheel to be locked to provide more traditional 4WD. This was a basic vehicle: tops for the doors and a roof (canvas or metal) were optional extras. In 1950, the lights moved from a position behind the grille to protruding through the grille.