the crossover unit includes a polyurethane pad having a slot extending downwardly and then laterally or horizontally beneath an overhanging lip . a wedge - shaped rubber insert or plug is received in the slot which not only closes the slot , but also resists deflection of the lip when heavy vehicles traverse the unit so that sufficient space is maintained beneath the lip for the protective accommodation of an electric power cable or hose . in a second embodiment the slot extends in opposite lateral directions between a pair of overhanging lips , the insert in this instance being received between the two lips so that space exists under the lips for two cables or hoses .