Abstract: A coupling system for a vehicle such as an articulated lorry and method of use thereof is provided. The articulated lorry includes at least a tractor unit and a trailer unit. The tractor unit has first coupling means provided on a fifth wheel which engages with second coupling means typically in the form of a kingpin on the trailer unit. The fifth wheel coupling means and the kingpin have one or more pneumatic and/or electrical supply lines provided therein which engage upon mechanical engagement of the fifth wheel coupling means and kingpin, thereby allowing pneumatic and/or electrical supply between said tractor unit and said trailer unit and/or vice versa. One of the fifth wheel coupling means or kingpin is provided with one or more annular protrusions on a coupling surface and the other is provided with complementary annular channels on a coupling surface.