§ 74.020  MIRRORS.
   Every motor vehicle, operated singly or when towing another vehicle, shall be equipped with a mirror having at least 3 square inches of reflecting surface, and so located as to reflect to the driver a view of the highway for a distance of at least 200 feet to the rear of the motor vehicle.
(ILCS Ch. 625, Act 5, § 12-502) ('64 Code, § 21-143)  Penalty, see § 70.999