All-new design double-shaft high torque engine created for use with Mini 4WD professional series racers. Motor decreases energy loss and provides high speed operating also on slopes and curves. Either end for the double-shaft features push fit brass pinion gears for efficient energy transmission. This engine may be used in official Tamiya Mini 4WD races. *Compatible chassis: Mini 4WD PRO show chassis (never appropriate for Dangun or non- PRO series racers)