PremiAir Hie's offers the most reliable & cost effective portable traffic light system on the market today. Used where temporary control of vehicular traffic is required, such as road or bridge works. The equipment is comprised of two electronic controllers known as MASTER and SLAVE mounted in a trailer unit that is capable of being split with each unit being positioned separately on the work site. The dual-trailer system allows the trailers to be connected together so that it can be towed as one individual unit. This capability allows the system to be towed to the job site using one vehicle. The Portable Traffic Signals are capable of operating under manual or automatic control and each separate unit is fully self-contained and powered by battery with a solar charging system. The fully lockable steel enclosure protects the controller and batteries from the elements and vandalism.