Abstract: A guide channel member for a shelving system permits a shelf with an electrical safety device mounted thereon to be vertically repositioned while minimizing potential damage to the wire leads and maintaining a neat appearance. The invention is particularly useful in mobile storage systems wherein movement of a movable unit is stocked, thereby preventing injury to a person standing next to the unit, when the safety device is actuated. The channel member defines a vertically oriented slot leading to a vertical passage. The wires pass from the safety device, through the slot, along the vertical passage, and to the system control unit. Storing excess wires in the channel member permits convenient repositioning of the shelf while protecting and hiding the wires.