its back end is centered with the metal bumper plate 84 on the loading dock 80 the display module 22 will be located several feet to the left of the trailer a first segment of conduit 88 extends between the transducer module 20 and the display module 22 and the cable 24 illustrated in fig1 will be located inside the first segment of conduit 88 a second segment of conduit 90 extends from the display module 22 and wires not shown are located inside the second segment of conduit 90 to supply power to the collision avoidance system of the present invention referring next to fig4 a tractor 92 is illustrated as it is backing a trailer 94 toward the loading dock 80 in addition to the display module 22 mounted on the loading dock 80 an enlarged display module 22 is also inset into fig4 above the loading dock 80 in fig4 the rear of the trailer 94 is indicated by the display 54 on the display module 22 to be seventeen feet from the metal bumper plate 84 on the loading dock 80 note that the first two digit numeric display 70 may be read by the driver of the tractor 92 by looking out the window of the cab.