When any implement of husbandry or road tractor is operated on a street or highway at a speed less than 20 miles per hour, there shall be displayed at all times during the operation a red flag at least 12 inches square carried on the vehicle at a height not less than ten nor more than 12 feet above the ground or at least one flashing amber signal lamp mounted as high as practicable, and of sufficient intensity to be visible to the rear for a distance of at least 500 feet in normal sunlight, provided that only the rear vehicle of a combination of the of the vehicles coupled together need display such a flag or lamp.
('73 Code, § 21-65) (Ord. 62-610, passed 10-1-62) Penalty, see § 70.999