Rolly Kid X-trac with brake and gears Specification.. This larger tractor comes with opening bonnet, three position adjustable seat, hand brake and two speed gears with gear stick selector. For ages 3 to an average 10 years. Mechanical features include a strong 12mm thick rear axle, covered integral fixed wheel chain drive, a pedal crank with eccentric bearing chain tensioning system and anti slip pedals,and a heavy duty front axle with suspension.