A sulky shall consist of the following parts which are attached to one another in such a way that they remain together during normal use and testing: Arch; Two forks; Seat and seat plate; Two shafts; Two stirrups; and Two wheels with tires and wheel covers. The arch under §A(1) of this regulation shall be: Parallel to the ground; Not less than 28 inches or more than 35 inches from the ground when measured with the wheels and tires attached; Not less than 1 inch higher than the top of the wheel and tire; Not less than 47 inches or more than 56 inches wide when measured from the inside at the point of the axle nuts; and Not more than 76 inches from the point the shaft is attached to the arch to the center line of the harness where the horse is hitched, as measured along the shaft when the sulky is attached to the horse. A fork under §A(2) of this regulation shall be: Attached to a side of the arch and to the shaft on that side of the arch; and Separated from the other fork by a distance, when measured at the axle nuts, which is 6 inches wider than the inside measurement between the shafts when the separation between the shafts is measured at the front of the arch. The seat plate under §A(3) of this regulation shall: Be mounted on the arch; Have not more than a 6-inch difference in the measurement of the distance from the ground to the plate than the distance from the ground to the heel of the stirrup when the sulky is hitched at 54 inches; and Have a padded seat securely attached in a fixed position, the back of which may not be: Higher than 4 inches; or More than 19 inches from the front of the arch. The shafts under §A(4) of this regulation: Shall be independent of one another; Shall be attachable to the horse either with: Quick-hitch fixtures accompanied by safety straps, or Conventional tie-downs; Shall be separated from each other by not less than 42 inches or more than 50 inches when measured at the front of the arch; and May not, when attached to the horse: Project beyond the shoulder of the horse, and Be higher than the withers of the horse. The stirrups under §A(5) of this regulation shall be: Not more than 8 inches wide; and Attached, one to the inside of each shaft, at a point where the stirrups are separated from each other by not less than 30 inches. The wheels under §A(6) of this regulation each shall be: Between 26 inches and 28 inches in diameter when measured from the outside edges of the tire; Covered with light and durable unicolor or colorless wheel disc covers; and When necessary, inhibited from discharging residue from the tire by the use of a mud fender securely attached to the sulky. When enforcing the specifications under this regulation, the judges, in determining the safety, fitness, and reliability of a sulky, may rely on: Manufacturers' certifications; and Current inspection stickers affixed by manufacturers' representatives.