A new, large-scale, very low dose cabinet X-ray system has been installed at the newly- completed commercial border crossing facility located at Otay Mesa, California, a few miles south of San Diego. The system has two separate 450 kV flying-spot X-ray sources, each with its own sets of transmission and backscatter detectors. The sources are located below grade, and are arranged to illuminate the undercarriage and the sides of the truck symmetrically from below. This geometry allows close proximity of the sources to the truck, resulting in improved imaging performance. The point-by-point mapping sequence of a flying-spot scan enables both transmission and backscatter images to be obtained simultaneously. The system is intended primarily for the inspection of empty trucks, but it can also be used to inspect loaded vehicles up to 80,000 pounds gross weight and 65' long. It will be operated by U.S. Customs Service personnel. The system and its planned operations are described. Key issues involve vehicle and driver logistics, vehicle handling within the X-ray facility, throughput, ease of use, and radiation safety. The results of radiation survey measurements and initial test images will be presented.