P.I.R. AUTOMATIC LIGHT CONTROL UNIT This Unit is intended to automatically switch the Internal Lights On and Off in the back of Box Vans, Curtain Sided Vehicles, Trailers etc; thus saving valuable Battery Power be preventing Lights being Left On in error. The Lights are automatically Switched On in the Rear of the Vehicle as soon as the Driver gains entry and Extinguished upon the Driver leaving by means of an Infra Red Detector.