Class 1 is an open-wheel unlimited design with one or two seats that competes in the SCORE off-road race series like the Baja and San Felipe, and class Unlimited 1500 in Best in the Desert series. Typically, steering or turning brakes are permitted. These vehicles are similar in construction to Trick Trucks and Trophy Trucks but have a rear engine location and IRS (independent rear suspension). Engines must be normally aspirated and there are no displacement limitations. However, there are no production bodied vehicles allowed in this class.