625 ILCS 5/1-142.05: Maxi-cube vehicle.

A combination of vehicles consisting of a truck-tractor, upon which is mounted a separable cargo carrying semi-trailer, and a trailing unit that is attached by a pintle hook or similar connection, with the separable cargo carrying semi-trailer designed so as to be loaded and unloaded through the trailing unit, except that the entire combination shall not exceed 65 feet in length and that neither the semi-trailer nor the trailing unit in the combination shall by itself exceed 34 feet in length.