Whenever the load upon any vehicle extends to the rear four feet or more beyond the bed or body of such vehicle, there shall be displayed at the extreme rear end of the load, at the times specified in Section 438.02, a red light or lantern plainly visible from a distance of at least 500 feet to the side and rear. The red light or lantern required by this section is in addition to the red rear light required upon every vehicle. At any other time there shall be displayed at the extreme rear end of such load a red flag or cloth not less than sixteen inches square.
(ORC 4513.09)