This is an optional Incision Axial Capra and SCX10 III Portal Overdrive Gear Set, designed for use with for SCX10-III and Axial Capra Axles. These gears have a 1.33:1 gear ratio compared to 1.92:1 gear ratio of Standard Gears and are intended use in the front axle, or front and rear axle for higher speed applications.