Cover, gear (upper & lower) (1)/ dust plug (1)/ 3x6mm CS (3) (for single motor installation, use with motor plate 3997X) E-MAXX GEAR COVER AND MOTOR PLATE FOR SINGLE MOTOR INSTALLATION: The E-Maxx was designed from the ground-up to handle extreme brushless torque and power. Traxxas makes it easy to convert from dual motors to a single brushless motor setup. Choose your favorite electric power plant and bolt it in using the Traxxas single motor gear cover and blue-anodized aluminum motor plate. The two-piece gear cover keeps dirt and debris out, while allowing easy access to the pinion and spur gear. A removable plug makes slipper clutch adjustments easy. These parts give your brushless install a clean factory fit and finish. Fits E-Maxx models 3905 and 3903