Indiana Code Title 9. Motor Vehicles § 9-21-9-2

Sec. 2. Whenever a vehicle is moved, operated, or driven on a highway that is open for vehicular travel, the vehicle shall display a triangular slow moving vehicle emblem mounted as near as is practicable to the center of mass and at an approximate height of not less than two (2) and not more than ten (10) feet from level ground or pavement surface.  The emblem shall be mounted so as to be entirely visible from the rear, day or night.  The emblem and the emblem's position of mounting on the vehicle must substantially adhere to the recommendations of the: