(1)    No person may operate on a highway any vehicle or equipment, any implement of husbandry, any animal-drawn vehicle, or any other machinery, including all road machinery, that usually travels at speeds of less than 25 miles per hour or any vehicle operated under a special restricted operator’s license issued under s. 343.135 or any lightweight utility vehicle, as defined in s. 346.94 (21) (a) 2., unless there is displayed on the most practicable visible rear area of the vehicle or combination of vehicles, a slow moving vehicle (SMV) emblem as described in and displayed as provided in sub. (2). Any towed vehicle or machine is exempt from this provision if the towing vehicle is visible from the rear and is in compliance with this section. All road machinery is excluded when it is engaged in actual construction or maintenance work either guarded by a flagman or clearly visible warning signs. The requirement of the emblem shall be in addition to any lighting devices required or permitted by law. Mopeds and motor bicycles are excluded from the provisions of this section unless they are operated under a special restricted operator’s license issued under s. 343.135. Electric scooters, electric personal assistive mobility devices, and personal delivery devices are excluded from the provisions of this section. The SMV emblem need not be displayed on vehicles moving directly across the highway.

   (2)   Standards and specifications for the design and position of mounting of the SMV emblem shall be established by rule by the secretary. The standards and specifications for SMV emblems shall correlate with and, so far as possible, conform with those approved by the American society of agricultural engineers. The secretary shall submit such standards and specifications, and any subsequent changes therein, to the assembly and senate committees having jurisdiction over transportation matters as determined by the speaker of the assembly and the president of the senate acting jointly for their approval.

   (3)   No person shall display such emblem on a roadway, except as provided in sub. (1), nor on roadside stationary objects such as mailboxes or signposts and no such emblem shall be used as a clearance marker for wide vehicles. No slow moving vehicle actually engaged in construction or maintenance guarded by a flagman or clearly visible warning signs need remove the slow moving vehicle emblem.

   (4)   No person shall display such emblem on any vehicle or equipment not specified in sub. (1).

   (5)   This section does not apply to any vehicle or combination of vehicles to the left rear of which is attached a yellow or amber flashing light at least 4 inches in diameter, except to an implement of husbandry.